| Donnington Castle | Berkshire | England | English Heritage | Partial ruin | Free, open access | 4.4 (1,595) |
| Windsor Castle | Berkshire | England | Royal Collection Trust | Intact | Staffed, ticketed | 4.7 (64,907) |
| Beeston Castle | Cheshire | England | English Heritage | Ruin | Staffed, ticketed | 4.5 (2,985) |
| Chester Castle: Agricola Tower and Castle Walls | Cheshire | England | English Heritage | Partial ruin | Limited tour days | 4.3 (377) |
| Halton Castle | Cheshire | England | Norton Priory Museum Trust (Duchy of Lancaster) | Ruin | Limited tour days | 4.3 (687) |
| Peckforton Castle | Cheshire | England | Peckforton Castle Hotel (Naylor family) | Intact | Hotel guests only | 4.4 (2,584) |
| Caerhays Castle | Cornwall | England | Williams family (Caerhays Estate) | Intact | Limited tour days | 4.5 (389) |
| Cromwell's Castle | Cornwall | England | English Heritage | Partial ruin | Free, open access | 4.7 (68) |
| King Charles's Castle | Cornwall | England | English Heritage | Ruin | Free, open access | 4.7 (45) |
| Launceston Castle | Cornwall | England | English Heritage | Partial ruin | Staffed, ticketed | 4.4 (1,082) |
| Pendennis Castle | Cornwall | England | English Heritage | Intact | Staffed, ticketed | — |
| Restormel Castle | Cornwall | England | English Heritage | Partial ruin | Staffed, ticketed | 4.5 (1,156) |
| St Catherine's Castle | Cornwall | England | English Heritage | Ruin | Free, open access | 4.4 (549) |
| St Mawes Castle | Cornwall | England | English Heritage | Intact | Staffed, ticketed | 4.5 (1,854) |
| St Michael's Mount | Cornwall | England | National Trust | Intact | Staffed, ticketed | 4.6 (2,961) |
| Star Castle | Cornwall | England | Star Castle Hotel | Intact | Hotel guests only | 4.5 (233) |
| Tintagel Castle | Cornwall | England | English Heritage | Ruin | Staffed, ticketed | 4.6 (18,853) |
| Auckland Castle | County Durham | England | The Auckland Project | Intact | Staffed, ticketed | 4.6 (1,047) |
| Barnard Castle | County Durham | England | English Heritage | Partial ruin | Staffed, ticketed | — |
| Bowes Castle | County Durham | England | English Heritage | Partial ruin | Free, open access | 4.4 (361) |
| Brancepeth Castle | County Durham | England | Dobson family (private) | Intact | Limited tour days | 4.5 (446) |
| Durham Castle | County Durham | England | University College, Durham University | Intact | Limited tour days | 4.6 (2,087) |
| Lumley Castle | County Durham | England | Lumley Castle Hotel (No Ordinary Hotels) | Intact | Hotel guests only | 4.5 (3,560) |
| Raby Castle | County Durham | England | Raby Estates (Lord Barnard) | Intact | Staffed, ticketed | 4.6 (3,926) |
| Walworth Castle | County Durham | England | Walworth Castle Hotel | Intact | Hotel guests only | 4.4 (1,351) |
| Appleby Castle | Cumbria | England | Appleby Castle Hotel (private) | Intact | Staffed, ticketed | 4.2 (523) |
| Brough Castle | Cumbria | England | English Heritage | Ruin | Free, open access | 4.5 (992) |
| Brougham Castle | Cumbria | England | English Heritage | Partial ruin | Staffed, ticketed | 4.6 (1,351) |
| Carlisle Castle | Cumbria | England | English Heritage | Intact | Staffed, ticketed | 4.4 (4,695) |
| Dalton Castle | Cumbria | England | National Trust | Intact | Limited tour days | 4.1 (104) |
| Egremont Castle | Cumbria | England | Cumberland Council | Ruin | Free, open access | 4.3 (248) |
| Kendal Castle | Cumbria | England | Westmorland & Furness Council | Ruin | Free, open access | — |
| Lowther Castle | Cumbria | England | Lowther Castle & Gardens Trust | Ruin | Staffed, ticketed | 4.6 (4,609) |
| Muncaster Castle | Cumbria | England | Pennington family | Intact | Staffed, ticketed | — |
| Pendragon Castle | Cumbria | England | Private owner | Ruin | Free, open access | — |
| Penrith Castle | Cumbria | England | English Heritage | Ruin | Free, open access | 4.3 (758) |
| Piel Castle | Cumbria | England | English Heritage | Partial ruin | Free, open access | 4.8 (213) |
| Sizergh Castle | Cumbria | England | National Trust | Intact | Staffed, ticketed | 4.6 (5,100) |
| Wray Castle | Cumbria | England | National Trust | Intact | Grounds only | 4.1 (5,707) |
| Bolsover Castle | Derbyshire | England | English Heritage | Intact | Staffed, ticketed | 4.6 (6,758) |
| Duffield Castle | Derbyshire | England | National Trust | Ruin | Free, open access | 3.3 (222) |
| Peveril Castle | Derbyshire | England | English Heritage | Partial ruin | Staffed, ticketed | 4.4 (1,654) |
| Berry Pomeroy Castle | Devon | England | English Heritage | Partial ruin | Staffed, ticketed | 4.6 (1,444) |
| Castle Drogo | Devon | England | National Trust | Intact | Staffed, ticketed | — |
| Compton Castle | Devon | England | National Trust | Intact | Limited tour days | 4.2 (718) |
| Dartmouth Castle | Devon | England | English Heritage | Intact | Staffed, ticketed | 4.5 (2,862) |
| Kingswear Castle | Devon | England | Landmark Trust | Intact | Hotel guests only | 4 (65) |
| Lydford Castle and Saxon Town | Devon | England | English Heritage | Partial ruin | Free, open access | 4.4 (248) |
| Marisco Castle | Devon | England | National Trust | Partial ruin | Free, open access | — |
| Okehampton Castle | Devon | England | English Heritage | Ruin | Free, open access | 4.4 (973) |
| Powderham Castle | Devon | England | Earl of Devon (Powderham Estate) | Intact | Staffed, ticketed | 4.5 (2,746) |
| Tiverton Castle | Devon | England | Gordon family | Partial ruin | Limited tour days | 4.3 (158) |
| Totnes Castle | Devon | England | English Heritage | Partial ruin | Staffed, ticketed | 4.2 (1,449) |
| Watermouth Castle | Devon | England | Escapade Group Ltd | Intact | Staffed, ticketed | 4.5 (2,301) |
| Christchurch Castle and Norman House | Dorset | England | English Heritage | Ruin | Free, open access | 4.5 (1,122) |
| Corfe Castle | Dorset | England | National Trust | Ruin | Staffed, ticketed | — |
| Lulworth Castle | Dorset | England | English Heritage | Partial ruin | Staffed, ticketed | 4.6 (2,097) |
| Portland Castle | Dorset | England | English Heritage | Intact | Staffed, ticketed | 4.4 (2,166) |
| Sherborne Castle | Dorset | England | Wingfield Digby family | Intact | Staffed, ticketed | — |
| Sherborne Old Castle | Dorset | England | English Heritage | Ruin | Free, open access | — |
| Skipsea Castle | East Riding of Yorkshire | England | English Heritage | Ruin | Free, open access | 3.6 (151) |
| Bodiam Castle | East Sussex | England | National Trust | Partial ruin | Staffed, ticketed | 4.7 (8,078) |
| Camber Castle | East Sussex | England | English Heritage | Partial ruin | Grounds only | 4.3 (336) |
| Hastings Castle | East Sussex | England | Hastings Borough Council (leased operator) | Ruin | Staffed, ticketed | 4.2 (2,756) |
| Herstmonceux Castle | East Sussex | England | Bader College (Queen's University Canada) | Intact | Staffed, ticketed | 4.5 (2,307) |
| Lewes Castle | East Sussex | England | Sussex Archaeological Society | Partial ruin | Staffed, ticketed | 4.5 (1,741) |
| Pevensey Castle | East Sussex | England | English Heritage | Partial ruin | Staffed, ticketed | 4.5 (2,660) |
| Rye Castle (Ypres Tower) | East Sussex | England | Rye Castle Museum | Intact | Staffed, ticketed | 4.5 (1,071) |
| Colchester Castle | Essex | England | Colchester City Council (Colchester Museums) | Intact | Staffed, ticketed | 4.5 (3,440) |
| Hadleigh Castle | Essex | England | English Heritage | Ruin | Free, open access | 4.6 (1,328) |
| Hedingham Castle | Essex | England | Lindsay family | Partial ruin | Staffed, ticketed | — |
| Mountfitchet Castle | Essex | England | Private family attraction | Partial ruin | Staffed, ticketed | — |
| Rayleigh Mount | Essex | England | National Trust | Ruin | Free, open access | 4.5 (121) |
| Berkeley Castle | Gloucestershire | England | Berkeley Castle Charitable Trust (Berkeley family) | Intact | Staffed, ticketed | 4.7 (1,752) |
| St Briavels Castle | Gloucestershire | England | English Heritage | Intact | Grounds only | 4.4 (437) |
| Sudeley Castle | Gloucestershire | England | Dent-Brocklehurst family (Lady Ashcombe) | Partial ruin | Staffed, ticketed | 4.6 (4,394) |
| Thornbury Castle | Gloucestershire | England | Thornbury Castle Hotel | Intact | Hotel guests only | 4.6 (1,255) |
| Tower of London | Greater London | England | Historic Royal Palaces | Intact | Staffed, ticketed | 4.7 (120,472) |
| Calshot Castle | Hampshire | England | English Heritage | Intact | Staffed, ticketed | 4.4 (585) |
| Hurst Castle | Hampshire | England | English Heritage | Intact | Staffed, ticketed | 4.4 (2,588) |
| Odiham Castle | Hampshire | England | Hampshire County Council | Ruin | Free, open access | 4.4 (775) |
| Portchester Castle | Hampshire | England | English Heritage | Partial ruin | Staffed, ticketed | 4.6 (5,228) |
| Southsea Castle | Hampshire | England | Portsmouth City Council | Intact | Staffed, ticketed | 4.5 (2,302) |
| Winchester Castle (Great Hall) | Hampshire | England | Hampshire County Council | Partial ruin | Staffed, ticketed | 4.4 (3,300) |
| Wolvesey Castle (Old Bishop's Palace) | Hampshire | England | English Heritage | Ruin | Free, open access | 4.4 (1,049) |
| Croft Castle | Herefordshire | England | National Trust | Intact | Staffed, ticketed | 4.6 (3,601) |
| Eastnor Castle | Herefordshire | England | Hervey-Bathurst family | Intact | Staffed, ticketed | — |
| Goodrich Castle | Herefordshire | England | English Heritage | Partial ruin | Staffed, ticketed | 4.7 (2,714) |
| Longtown Castle | Herefordshire | England | English Heritage | Partial ruin | Free, open access | 4.3 (328) |
| Wigmore Castle | Herefordshire | England | English Heritage | Ruin | Free, open access | 4.3 (176) |
| Berkhamsted Castle | Hertfordshire | England | English Heritage | Ruin | Free, open access | 4.5 (940) |
| Carisbrooke Castle | Isle of Wight | England | English Heritage | Intact | Staffed, ticketed | 4.6 (5,892) |
| Yarmouth Castle | Isle of Wight | England | English Heritage | Intact | Staffed, ticketed | 4.1 (435) |
| Chiddingstone Castle | Kent | England | Denys Eyre Bower Bequest (charitable trust) | Intact | Staffed, ticketed | — |
| Deal Castle | Kent | England | English Heritage | Intact | Staffed, ticketed | 4.4 (3,293) |
| Dover Castle | Kent | England | English Heritage | Intact | Staffed, ticketed | 4.7 (17,448) |
| Eynsford Castle | Kent | England | English Heritage | Ruin | Free, open access | 4.3 (633) |
| Hever Castle | Kent | England | Hever Castle Ltd (Guthrie family) | Intact | Staffed, ticketed | 4.8 (13,800) |
| Leeds Castle | Kent | England | Leeds Castle Foundation | Intact | Staffed, ticketed | 4.7 (13,646) |
| Lullingstone Castle | Kent | England | Hart Dyke family | Partial ruin | Staffed, ticketed | 4.5 (1,129) |
| Rochester Castle | Kent | England | Medway Council (English Heritage-owned) | Partial ruin | Staffed, ticketed | 4.6 (9,222) |
| Scotney Castle | Kent | England | National Trust | Partial ruin | Staffed, ticketed | 4.7 (6,963) |
| Sissinghurst Castle Garden | Kent | England | National Trust | Partial ruin | Staffed, ticketed | 4.6 (6,295) |
| St Leonard's Tower | Kent | England | English Heritage | Partial ruin | Grounds only | 3.9 (85) |
| Sutton Valence Castle | Kent | England | English Heritage | Ruin | Free, open access | 4.3 (192) |
| Tonbridge Castle | Kent | England | Tonbridge & Malling Borough Council | Partial ruin | Staffed, ticketed | 4.4 (2,043) |
| Upnor Castle | Kent | England | English Heritage | Intact | Staffed, ticketed | 4.3 (1,273) |
| Walmer Castle and Gardens | Kent | England | English Heritage | Intact | Staffed, ticketed | 4.7 (4,686) |
| Clitheroe Castle | Lancashire | England | Ribble Valley Borough Council / Lancashire County Council museum | Partial ruin | Staffed, ticketed | — |
| Lancaster Castle | Lancashire | England | Duchy of Lancaster | Intact | Staffed, ticketed | 4.5 (6,281) |
| Ashby de la Zouch Castle | Leicestershire | England | English Heritage | Partial ruin | Staffed, ticketed | 4.5 (1,279) |
| Belvoir Castle | Leicestershire | England | Duke of Rutland (Belvoir Castle Estate) | Intact | Staffed, ticketed | 4.4 (4,166) |
| Kirby Muxloe Castle | Leicestershire | England | English Heritage | Partial ruin | Limited tour days | 4.2 (649) |
| Bolingbroke Castle | Lincolnshire | England | English Heritage | Ruin | Free, open access | 4.5 (803) |
| Grimsthorpe Castle | Lincolnshire | England | Grimsthorpe & Drummond Castle Trust | Intact | Staffed, ticketed | 4.7 (1,114) |
| Lincoln Castle | Lincolnshire | England | Lincolnshire County Council | Partial ruin | Staffed, ticketed | 4.6 (11,827) |
| Tattershall Castle | Lincolnshire | England | National Trust | Intact | Staffed, ticketed | 4.5 (2,771) |
| Baconsthorpe Castle | Norfolk | England | English Heritage | Ruin | Free, open access | 4.5 (560) |
| Burgh Castle Roman Fort | Norfolk | England | English Heritage | Ruin | Free, open access | 4.5 (916) |
| Caister Castle | Norfolk | England | Private owner | Partial ruin | Staffed, ticketed | 4.4 (565) |
| Castle Acre Castle and Bailey Gate | Norfolk | England | English Heritage | Ruin | Free, open access | — |
| Castle Rising Castle | Norfolk | England | Lord Howard of Rising (English Heritage custody) | Partial ruin | Staffed, ticketed | 4.6 (2,529) |
| Norwich Castle | Norfolk | England | Norfolk Museums Service (Norfolk County Council) | Intact | Staffed, ticketed | 4.3 (3,762) |
| Weeting Castle | Norfolk | England | English Heritage | Ruin | Free, open access | 4.2 (278) |
| Bolton Castle | North Yorkshire | England | Lord Bolton (Scrope family) | Partial ruin | Staffed, ticketed | — |
| Cawood Castle | North Yorkshire | England | Landmark Trust | Partial ruin | Hotel guests only | 4.6 (9) |
| Clifford's Tower, York | North Yorkshire | England | English Heritage | Partial ruin | Staffed, ticketed | 4.3 (5,963) |
| Hazlewood Castle | North Yorkshire | England | Hazlewood Castle & Spa (hotel) | Intact | Hotel guests only | 4.3 (1,370) |
| Helmsley Castle | North Yorkshire | England | English Heritage | Partial ruin | Staffed, ticketed | 4.5 (3,038) |
| Knaresborough Castle | North Yorkshire | England | North Yorkshire Council (Duchy of Lancaster owned) | Ruin | Free, open access | 4.6 (4,880) |
| Middleham Castle | North Yorkshire | England | English Heritage | Partial ruin | Staffed, ticketed | 4.6 (1,812) |
| Pickering Castle | North Yorkshire | England | English Heritage | Partial ruin | Staffed, ticketed | 4.4 (1,486) |
| Richmond Castle | North Yorkshire | England | English Heritage | Partial ruin | Staffed, ticketed | 4.6 (2,969) |
| Ripley Castle | North Yorkshire | England | Ingilby family (Ripley Castle Estate) | Intact | Limited tour days | 4.5 (2,839) |
| Scarborough Castle | North Yorkshire | England | English Heritage | Partial ruin | Staffed, ticketed | 4.6 (8,836) |
| Skipton Castle | North Yorkshire | England | Fattorini family | Intact | Staffed, ticketed | 4.5 (5,454) |
| Spofforth Castle | North Yorkshire | England | English Heritage | Ruin | Free, open access | 4.5 (850) |
| Rockingham Castle | Northamptonshire | England | Saunders Watson family | Intact | Staffed, ticketed | 4.6 (1,025) |
| Alnwick Castle | Northumberland | England | Northumberland Estates (Duke of Northumberland) | Intact | Staffed, ticketed | 4.6 (15,737) |
| Aydon Castle | Northumberland | England | English Heritage | Intact | Staffed, ticketed | 4.4 (514) |
| Bamburgh Castle | Northumberland | England | Armstrong family | Intact | Staffed, ticketed | 4.7 (19,110) |
| Belsay Hall, Castle and Gardens | Northumberland | England | English Heritage | Intact | Staffed, ticketed | 4.7 (2,677) |
| Berwick-upon-Tweed Castle and Ramparts | Northumberland | England | English Heritage | Ruin | Free, open access | 4.5 (600) |
| Chillingham Castle | Northumberland | England | Sir Humphry Wakefield family | Intact | Staffed, ticketed | — |
| Dunstanburgh Castle | Northumberland | England | English Heritage | Ruin | Staffed, ticketed | 4.6 (2,357) |
| Edlingham Castle | Northumberland | England | English Heritage | Ruin | Free, open access | 4.6 (576) |
| Etal Castle | Northumberland | England | English Heritage | Partial ruin | Free, open access | 4.3 (1,106) |
| Langley Castle | Northumberland | England | Langley Castle Hotel | Intact | Hotel guests only | 4.7 (1,279) |
| Lindisfarne Castle | Northumberland | England | National Trust | Intact | Staffed, ticketed | 4.5 (3,624) |
| Morpeth Castle | Northumberland | England | Landmark Trust | Partial ruin | Hotel guests only | 4.3 (24) |
| Norham Castle | Northumberland | England | English Heritage | Partial ruin | Free, open access | 4.5 (607) |
| Prudhoe Castle | Northumberland | England | English Heritage | Partial ruin | Free, open access | 4.2 (653) |
| Warkworth Castle and Hermitage | Northumberland | England | English Heritage | Partial ruin | Staffed, ticketed | 4.6 (4,082) |
| Newark Castle | Nottinghamshire | England | Newark & Sherwood District Council | Partial ruin | Free, open access | 4.5 (2,392) |
| Nottingham Castle | Nottinghamshire | England | Nottingham City Council | Partial ruin | Staffed, ticketed | 4.1 (6,227) |
| Broughton Castle | Oxfordshire | England | Lord Saye and Sele family | Intact | Limited tour days | 4.7 (763) |
| Deddington Castle | Oxfordshire | England | English Heritage | Ruin | Free, open access | 3.6 (135) |
| Oxford Castle & Prison | Oxfordshire | England | Continuum Attractions | Partial ruin | Staffed, ticketed | 4.4 (7,491) |
| Oakham Castle | Rutland | England | Rutland County Council | Partial ruin | Staffed, ticketed | 4.5 (1,147) |
| Acton Burnell Castle | Shropshire | England | English Heritage | Partial ruin | Free, open access | 4.5 (599) |
| Clun Castle | Shropshire | England | English Heritage | Partial ruin | Free, open access | 4.4 (950) |
| Hopton Castle | Shropshire | England | Hopton Castle Preservation Trust | Partial ruin | Free, open access | 4.7 (276) |
| Ludlow Castle | Shropshire | England | Earl of Powis (Powis Castle Estates) | Ruin | Staffed, ticketed | 4.6 (6,317) |
| Moreton Corbet Castle | Shropshire | England | English Heritage | Ruin | Free, open access | 4.6 (790) |
| Shrewsbury Castle | Shropshire | England | Shropshire Council (Soldiers of Shropshire Museum) | Intact | Staffed, ticketed | 4.5 (1,178) |
| Stokesay Castle | Shropshire | England | English Heritage | Intact | Staffed, ticketed | 4.7 (2,486) |
| Whittington Castle | Shropshire | England | Whittington Castle Preservation Trust | Ruin | Free, open access | 4.6 (641) |
| Dunster Castle | Somerset | England | National Trust | Intact | Staffed, ticketed | 4.7 (8,645) |
| Farleigh Hungerford Castle | Somerset | England | English Heritage | Partial ruin | Staffed, ticketed | 4.6 (1,149) |
| Nunney Castle | Somerset | England | English Heritage | Partial ruin | Grounds only | 4.7 (696) |
| Taunton Castle | Somerset | England | South West Heritage Trust | Partial ruin | Staffed, ticketed | — |
| Conisbrough Castle | South Yorkshire | England | English Heritage | Partial ruin | Staffed, ticketed | 4.5 (2,526) |
| Stafford Castle | Staffordshire | England | Stafford Borough Council | Ruin | Free, open access | 4.5 (1,552) |
| Tamworth Castle | Staffordshire | England | Tamworth Borough Council | Intact | Staffed, ticketed | 4.6 (2,138) |
| Tutbury Castle | Staffordshire | England | Duchy of Lancaster (leased to Bespoke Inns) | Ruin | Limited tour days | 4.4 (923) |
| Bungay Castle | Suffolk | England | Bungay Castle Trust | Ruin | Free, open access | 4.1 (346) |
| Framlingham Castle | Suffolk | England | English Heritage | Partial ruin | Staffed, ticketed | 4.5 (5,418) |
| Orford Castle | Suffolk | England | English Heritage | Intact | Staffed, ticketed | 4.5 (1,513) |
| Farnham Castle Keep | Surrey | England | English Heritage | Partial ruin | Grounds only | 4.5 (762) |
| Guildford Castle | Surrey | England | Guildford Borough Council | Partial ruin | Staffed, ticketed | 4.6 (3,084) |
| Hylton Castle | Tyne and Wear | England | English Heritage | Partial ruin | Limited tour days | 4.5 (724) |
| Newcastle Castle | Tyne and Wear | England | Heart of the City Partnership (charity) | Partial ruin | Staffed, ticketed | 4.5 (3,366) |
| Tynemouth Priory and Castle | Tyne and Wear | England | English Heritage | Ruin | Staffed, ticketed | 4.6 (3,707) |
| Astley Castle | Warwickshire | England | Landmark Trust | Partial ruin | Hotel guests only | 4.5 (223) |
| Kenilworth Castle and Elizabethan Garden | Warwickshire | England | English Heritage | Partial ruin | Staffed, ticketed | 4.7 (7,615) |
| Warwick Castle | Warwickshire | England | Merlin Entertainments | Intact | Staffed, ticketed | 4.6 (26,516) |
| Dudley Castle | West Midlands | England | Dudley Zoological Society (Dudley Zoo & Castle) | Ruin | Staffed, ticketed | 4.4 (11,996) |
| Amberley Castle | West Sussex | England | Amberley Castle Hotel (Relais & Chateaux) | Intact | Hotel guests only | 4.7 (878) |
| Arundel Castle | West Sussex | England | Arundel Castle Trustees (Duke of Norfolk) | Intact | Staffed, ticketed | 4.7 (12,750) |
| Bramber Castle | West Sussex | England | English Heritage | Ruin | Free, open access | 4.5 (955) |
| Pontefract Castle | West Yorkshire | England | Wakefield Council | Ruin | Free, open access | 4.5 (2,001) |
| Sandal Castle | West Yorkshire | England | Wakefield Council | Ruin | Free, open access | 4.5 (2,603) |
| Ludgershall Castle and Cross | Wiltshire | England | English Heritage | Ruin | Free, open access | 4.3 (457) |
| Old Sarum | Wiltshire | England | English Heritage | Ruin | Staffed, ticketed | 4.5 (3,557) |
| Old Wardour Castle | Wiltshire | England | English Heritage | Partial ruin | Staffed, ticketed | 4.7 (1,903) |
| Hartlebury Castle | Worcestershire | England | Hartlebury Castle Preservation Trust | Intact | Staffed, ticketed | 4.7 (972) |
| Antrim Castle Gardens | County Antrim | Northern Ireland | Antrim & Newtownabbey Borough Council | Ruin | Grounds only | 4.7 (190) |
| Ballygally Castle | County Antrim | Northern Ireland | Hastings Hotels | Intact | Hotel guests only | 4.6 (1,712) |
| Belfast Castle | County Antrim | Northern Ireland | Belfast City Council | Intact | Staffed, ticketed | 4.5 (6,896) |
| Carrickfergus Castle | County Antrim | Northern Ireland | Department for Communities (Historic Environment Division) | Intact | Staffed, ticketed | 4.5 (6,303) |
| Dunluce Castle | County Antrim | Northern Ireland | Department for Communities (Historic Environment Division) | Ruin | Staffed, ticketed | 4.6 (8,865) |
| Dunseverick Castle | County Antrim | Northern Ireland | National Trust | Ruin | Free, open access | 4.4 (1,478) |
| Glenarm Castle | County Antrim | Northern Ireland | Private (Glenarm Estate / McDonnell family) | Intact | Limited tour days | 4.5 (1,977) |
| Castle Ward | County Down | Northern Ireland | National Trust | Intact | Staffed, ticketed | 4.6 (2,977) |
| Dundrum Castle | County Down | Northern Ireland | Department for Communities (Historic Environment Division) | Ruin | Free, open access | 4.6 (952) |
| Greencastle Royal Castle | County Down | Northern Ireland | Department for Communities (Historic Environment Division) | Ruin | Limited tour days | 4.1 (116) |
| Hillsborough Castle | County Down | Northern Ireland | Historic Royal Palaces | Intact | Staffed, ticketed | 4.7 (2,165) |
| Jordan's Castle | County Down | Northern Ireland | Department for Communities (Historic Environment Division) | Partial ruin | Limited tour days | 3.9 (29) |
| Kilclief Castle | County Down | Northern Ireland | Department for Communities (Historic Environment Division) | Partial ruin | Limited tour days | 4.3 (23) |
| Killyleagh Castle | County Down | Northern Ireland | Private (Hamilton family) | Intact | Grounds only | 4.6 (181) |
| Narrow Water Castle | County Down | Northern Ireland | Private (Hall family) | Intact | Limited tour days | 4.7 (116) |
| Narrow Water Keep | County Down | Northern Ireland | Department for Communities (Historic Environment Division) | Partial ruin | Limited tour days | 4.5 (134) |
| Enniskillen Castle | County Fermanagh | Northern Ireland | Fermanagh & Omagh District Council (Enniskillen Castle Museums) | Partial ruin | Staffed, ticketed | 4.5 (1,746) |
| Monea Castle | County Fermanagh | Northern Ireland | Department for Communities (Historic Environment Division) | Ruin | Free, open access | 4.6 (131) |
| Tully Castle | County Fermanagh | Northern Ireland | Department for Communities (Historic Environment Division) | Ruin | Free, open access | 4.5 (311) |
| Balmoral Castle | Aberdeenshire | Scotland | Royal Family (Balmoral Estates) | Intact | Staffed, ticketed | 4.3 (7,255) |
| Braemar Castle | Aberdeenshire | Scotland | Braemar Community Ltd (community trust) | Intact | Staffed, ticketed | 4.4 (1,052) |
| Castle Fraser | Aberdeenshire | Scotland | National Trust for Scotland | Intact | Staffed, ticketed | 4.7 (1,998) |
| Corgarff Castle | Aberdeenshire | Scotland | Historic Environment Scotland | Intact | Staffed, ticketed | 4.2 (190) |
| Craigievar Castle | Aberdeenshire | Scotland | National Trust for Scotland | Intact | Staffed, ticketed | 4.6 (1,195) |
| Craigston Castle | Aberdeenshire | Scotland | Urquhart family | Intact | Limited tour days | 4.9 (57) |
| Crathes Castle | Aberdeenshire | Scotland | National Trust for Scotland | Intact | Staffed, ticketed | 4.6 (3,225) |
| Delgatie Castle | Aberdeenshire | Scotland | Delgatie Castle Trust | Intact | Staffed, ticketed | — |
| Drum Castle | Aberdeenshire | Scotland | National Trust for Scotland | Intact | Staffed, ticketed | 4.6 (1,574) |
| Dunnottar Castle | Aberdeenshire | Scotland | Dunecht Estates | Ruin | Staffed, ticketed | 4.8 (13,279) |
| Fyvie Castle | Aberdeenshire | Scotland | National Trust for Scotland | Intact | Staffed, ticketed | 4.7 (1,691) |
| Glenbuchat Castle | Aberdeenshire | Scotland | Historic Environment Scotland | Ruin | Grounds only | 3.9 (55) |
| Huntly Castle | Aberdeenshire | Scotland | Historic Environment Scotland | Ruin | Staffed, ticketed | 4.6 (1,013) |
| Kildrummy Castle | Aberdeenshire | Scotland | Historic Environment Scotland | Ruin | Staffed, ticketed | 4.6 (275) |
| Kinnaird Head Castle Lighthouse | Aberdeenshire | Scotland | Historic Environment Scotland | Intact | Limited tour days | 4.7 (126) |
| Tolquhon Castle | Aberdeenshire | Scotland | Historic Environment Scotland | Ruin | Staffed, ticketed | — |
| Edzell Castle and Garden | Angus | Scotland | Historic Environment Scotland | Ruin | Staffed, ticketed | 4.6 (225) |
| Glamis Castle | Angus | Scotland | Strathmore Estates (Earl of Strathmore) | Intact | Staffed, ticketed | 4.7 (6,207) |
| Barcaldine Castle | Argyll and Bute | Scotland | Private owners (B&B) | Intact | Hotel guests only | 4.9 (266) |
| Carnasserie Castle | Argyll and Bute | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4.8 (462) |
| Castle Stalker | Argyll and Bute | Scotland | Allward family (private) | Intact | Limited tour days | 4.5 (850) |
| Castle Sween | Argyll and Bute | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4.6 (184) |
| Duart Castle | Argyll and Bute | Scotland | Clan Maclean (Maclean family) | Intact | Staffed, ticketed | 4.6 (1,740) |
| Dunstaffnage Castle and Chapel | Argyll and Bute | Scotland | Historic Environment Scotland | Partial ruin | Staffed, ticketed | 4.5 (1,532) |
| Glengorm Castle | Argyll and Bute | Scotland | Nelson family (B&B/self-catering) | Intact | Hotel guests only | 4.8 (257) |
| Inveraray Castle | Argyll and Bute | Scotland | Argyll Estates (Duke of Argyll) | Intact | Staffed, ticketed | 4.6 (6,053) |
| Kilchurn Castle | Argyll and Bute | Scotland | Historic Environment Scotland | Ruin | Grounds only | 4.6 (1,974) |
| Kilmartin Castle | Argyll and Bute | Scotland | Private owners (boutique B&B) | Intact | Hotel guests only | 4.9 (96) |
| Rothesay Castle | Argyll and Bute | Scotland | Historic Environment Scotland | Partial ruin | Staffed, ticketed | 4.4 (517) |
| Skipness Castle and Chapel | Argyll and Bute | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4.7 (372) |
| Stonefield Castle Hotel | Argyll and Bute | Scotland | Hotel (Bespoke Hotels) | Intact | Hotel guests only | 4.5 (826) |
| Craigmillar Castle | City of Edinburgh | Scotland | Historic Environment Scotland | Partial ruin | Staffed, ticketed | 4.7 (3,081) |
| Edinburgh Castle | City of Edinburgh | Scotland | Historic Environment Scotland | Intact | Staffed, ticketed | 4.6 (107,504) |
| Alloa Tower | Clackmannanshire | Scotland | National Trust for Scotland | Intact | Staffed, ticketed | 4.4 (272) |
| Castle Campbell | Clackmannanshire | Scotland | Historic Environment Scotland | Partial ruin | Staffed, ticketed | 4.7 (1,000) |
| Clackmannan Tower | Clackmannanshire | Scotland | Historic Environment Scotland | Partial ruin | Grounds only | 4.5 (189) |
| Menstrie Castle | Clackmannanshire | Scotland | National Trust for Scotland | Intact | Limited tour days | 4.3 (70) |
| Caerlaverock Castle | Dumfries and Galloway | Scotland | Historic Environment Scotland | Ruin | Staffed, ticketed | 4.6 (3,128) |
| Cardoness Castle | Dumfries and Galloway | Scotland | Historic Environment Scotland | Partial ruin | Staffed, ticketed | 4.4 (119) |
| Carsluith Castle | Dumfries and Galloway | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4.3 (179) |
| Castle Kennedy | Dumfries and Galloway | Scotland | Stair Estates (Earl of Stair) | Ruin | Grounds only | — |
| Drumcoltran Tower | Dumfries and Galloway | Scotland | Historic Environment Scotland | Partial ruin | Free, open access | 4.5 (73) |
| Drumlanrig Castle | Dumfries and Galloway | Scotland | Buccleuch Estates (Duke of Buccleuch) | Intact | Staffed, ticketed | 4.6 (2,006) |
| Lochmaben Castle | Dumfries and Galloway | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4 (223) |
| MacLellan's Castle | Dumfries and Galloway | Scotland | Historic Environment Scotland | Ruin | Staffed, ticketed | 4.2 (330) |
| Morton Castle | Dumfries and Galloway | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4.5 (299) |
| Orchardton Tower | Dumfries and Galloway | Scotland | Historic Environment Scotland | Partial ruin | Free, open access | 4.3 (175) |
| Threave Castle | Dumfries and Galloway | Scotland | Historic Environment Scotland | Partial ruin | Staffed, ticketed | 4.6 (373) |
| Broughty Castle | Dundee City | Scotland | Historic Environment Scotland | Intact | Staffed, ticketed | 4.5 (1,700) |
| Claypotts Castle | Dundee City | Scotland | Historic Environment Scotland | Intact | Limited tour days | 4.2 (163) |
| Dean Castle | East Ayrshire | Scotland | East Ayrshire Leisure Trust | Intact | Staffed, ticketed | 4.5 (3,229) |
| Loch Doon Castle | East Ayrshire | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4.5 (509) |
| Dirleton Castle | East Lothian | Scotland | Historic Environment Scotland | Ruin | Staffed, ticketed | 4.6 (1,264) |
| Hailes Castle | East Lothian | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4.4 (383) |
| Tantallon Castle | East Lothian | Scotland | Historic Environment Scotland | Ruin | Staffed, ticketed | 4.7 (2,763) |
| Blackness Castle | Falkirk | Scotland | Historic Environment Scotland | Partial ruin | Staffed, ticketed | 4.7 (4,624) |
| Aberdour Castle and Gardens | Fife | Scotland | Historic Environment Scotland | Partial ruin | Staffed, ticketed | 4.6 (1,334) |
| Kellie Castle | Fife | Scotland | National Trust for Scotland | Intact | Staffed, ticketed | 4.5 (874) |
| Ravenscraig Castle | Fife | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4.3 (775) |
| Scotstarvit Tower | Fife | Scotland | Historic Environment Scotland | Partial ruin | Grounds only | 4.2 (19) |
| St Andrews Castle | Fife | Scotland | Historic Environment Scotland | Ruin | Staffed, ticketed | 4.5 (4,393) |
| Crookston Castle | Glasgow City | Scotland | Historic Environment Scotland | Partial ruin | Free, open access | 4.4 (415) |
| Armadale Castle, Gardens & Museum | Highland | Scotland | Clan Donald Lands Trust / Armadale Estate Ltd | Ruin | Staffed, ticketed | 4.4 (1,451) |
| Castle Leod | Highland | Scotland | Earl of Cromartie / Clan Mackenzie | Intact | Limited tour days | 4.6 (182) |
| Castle of Mey | Highland | Scotland | The King's Foundation (Castle of Mey Trust) | Intact | Staffed, ticketed | 4.5 (1,513) |
| Castle of Old Wick | Highland | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4.4 (564) |
| Cawdor Castle | Highland | Scotland | Cawdor Estate (Dowager Countess Cawdor) | Intact | Staffed, ticketed | 4.6 (3,788) |
| Dornoch Castle Hotel | Highland | Scotland | Hotel (Dornoch Castle Hotel Ltd) | Intact | Hotel guests only | 4.3 (241) |
| Dunrobin Castle | Highland | Scotland | Sutherland Estates | Intact | Staffed, ticketed | 4.7 (9,485) |
| Dunvegan Castle | Highland | Scotland | MacLeod Estate | Intact | Staffed, ticketed | 4.4 (8,523) |
| Eilean Donan Castle | Highland | Scotland | Conchra Charitable Trust | Intact | Staffed, ticketed | 4.6 (26,890) |
| Inverlochy Castle | Highland | Scotland | Historic Environment Scotland | Ruin | Grounds only | 4.1 (2,013) |
| Inverlochy Castle Hotel | Highland | Scotland | Hotel (Inverlochy Castle Ltd) | Intact | Hotel guests only | 4.6 (512) |
| Inverness Castle (Inverness Castle Experience) | Highland | Scotland | High Life Highland (charity) | Intact | Staffed, ticketed | 4.1 (5,334) |
| Strome Castle | Highland | Scotland | National Trust for Scotland | Ruin | Free, open access | 4.4 (334) |
| Tulloch Castle Hotel | Highland | Scotland | Hotel (Bespoke Hotels) | Intact | Hotel guests only | 4.2 (665) |
| Urquhart Castle | Highland | Scotland | Historic Environment Scotland | Ruin | Staffed, ticketed | 4.5 (28,186) |
| Newark Castle | Inverclyde | Scotland | Historic Environment Scotland | Intact | Staffed, ticketed | 4.4 (660) |
| Crichton Castle | Midlothian | Scotland | Historic Environment Scotland | Ruin | Grounds only | 4.5 (223) |
| Dalhousie Castle Hotel | Midlothian | Scotland | Hotel (Dalhousie Castle Hotel & Spa) | Intact | Hotel guests only | 4.3 (1,162) |
| Melville Castle Hotel | Midlothian | Scotland | Hotel (Melville Castle Ltd) | Intact | Hotel guests only | 4.5 (1,040) |
| Auchindoun Castle | Moray | Scotland | Historic Environment Scotland | Ruin | Grounds only | 4.7 (301) |
| Ballindalloch Castle | Moray | Scotland | Macpherson-Grant family | Intact | Staffed, ticketed | 4.6 (957) |
| Balvenie Castle | Moray | Scotland | Historic Environment Scotland | Ruin | Staffed, ticketed | 4.4 (434) |
| Brodie Castle | Moray | Scotland | National Trust for Scotland | Intact | Staffed, ticketed | 4.5 (2,128) |
| Duffus Castle | Moray | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4.6 (1,227) |
| Spynie Palace | Moray | Scotland | Historic Environment Scotland | Ruin | Staffed, ticketed | 4.5 (253) |
| Kisimul Castle | Na h-Eileanan Siar | Scotland | Historic Environment Scotland | Partial ruin | Grounds only | 4.3 (99) |
| Brodick Castle | North Ayrshire | Scotland | National Trust for Scotland | Intact | Staffed, ticketed | 4.6 (1,951) |
| Kelburn Castle | North Ayrshire | Scotland | Kelburn Estate (Earl of Glasgow) | Intact | Staffed, ticketed | — |
| Lochranza Castle | North Ayrshire | Scotland | Historic Environment Scotland | Partial ruin | Free, open access | 4.5 (667) |
| Cubbie Roo's Castle | Orkney Islands | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4.6 (8) |
| Noltland Castle | Orkney Islands | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4.6 (94) |
| Balhousie Castle (Black Watch Castle & Museum) | Perth and Kinross | Scotland | The Black Watch Castle & Museum (charity) | Intact | Staffed, ticketed | 4.7 (1,482) |
| Balvaird Castle | Perth and Kinross | Scotland | Historic Environment Scotland | Partial ruin | Free, open access | 4.5 (257) |
| Blair Castle | Perth and Kinross | Scotland | Blair Charitable Trust (Atholl Estates) | Intact | Staffed, ticketed | 4.7 (3,539) |
| Burleigh Castle | Perth and Kinross | Scotland | Historic Environment Scotland | Partial ruin | Free, open access | 4.2 (159) |
| Castle Menzies | Perth and Kinross | Scotland | Menzies Charitable Trust (Clan Menzies) | Intact | Staffed, ticketed | 4.6 (757) |
| Drummond Castle | Perth and Kinross | Scotland | Grimsthorpe & Drummond Castle Trust | Intact | Grounds only | 4.7 (1,247) |
| Elcho Castle | Perth and Kinross | Scotland | Historic Environment Scotland | Partial ruin | Staffed, ticketed | 4.6 (100) |
| Fonab Castle Hotel | Perth and Kinross | Scotland | Hotel (Fonab Castle Hotel & Spa) | Intact | Hotel guests only | 4.5 (844) |
| Huntingtower Castle | Perth and Kinross | Scotland | Historic Environment Scotland | Intact | Staffed, ticketed | 4.5 (700) |
| Lochleven Castle | Perth and Kinross | Scotland | Historic Environment Scotland | Partial ruin | Staffed, ticketed | 4.7 (486) |
| Ferniehirst Castle | Scottish Borders | Scotland | Clan Kerr (Marquess of Lothian) | Intact | Limited tour days | 4.5 (55) |
| Floors Castle | Scottish Borders | Scotland | Roxburghe Estates (Duke of Roxburghe) | Intact | Staffed, ticketed | 4.6 (1,392) |
| Greenknowe Tower | Scottish Borders | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4.5 (94) |
| Hermitage Castle | Scottish Borders | Scotland | Historic Environment Scotland | Partial ruin | Staffed, ticketed | 4.6 (410) |
| Smailholm Tower | Scottish Borders | Scotland | Historic Environment Scotland | Intact | Staffed, ticketed | 4.5 (342) |
| Thirlestane Castle | Scottish Borders | Scotland | Thirlestane Castle Trust (Maitland family) | Intact | Staffed, ticketed | 4.7 (593) |
| Muness Castle | Shetland Islands | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4.6 (185) |
| Scalloway Castle | Shetland Islands | Scotland | Historic Environment Scotland | Ruin | Free, open access | 4.3 (208) |
| Culzean Castle | South Ayrshire | Scotland | National Trust for Scotland | Intact | Staffed, ticketed | 4.7 (5,071) |
| Dundonald Castle | South Ayrshire | Scotland | Historic Environment Scotland | Partial ruin | Staffed, ticketed | 4.5 (1,048) |
| Glenapp Castle | South Ayrshire | Scotland | Hotel (Glenapp Castle Ltd) | Intact | Hotel guests only | 4.8 (513) |
| Bothwell Castle | South Lanarkshire | Scotland | Historic Environment Scotland | Ruin | Staffed, ticketed | 4.3 (886) |
| Cadzow Castle | South Lanarkshire | Scotland | Historic Environment Scotland | Ruin | Grounds only | 3.6 (48) |
| Craignethan Castle | South Lanarkshire | Scotland | Historic Environment Scotland | Ruin | Grounds only | 4.5 (224) |
| Crossbasket Castle | South Lanarkshire | Scotland | Hotel (Crossbasket Castle Ltd) | Intact | Hotel guests only | 4.7 (796) |
| Doune Castle | Stirling | Scotland | Historic Environment Scotland | Intact | Staffed, ticketed | 4.5 (7,568) |
| Stirling Castle | Stirling | Scotland | Historic Environment Scotland | Intact | Staffed, ticketed | 4.6 (34,809) |
| Dumbarton Castle | West Dunbartonshire | Scotland | Historic Environment Scotland | Partial ruin | Staffed, ticketed | 4.5 (2,124) |
| Coity Castle | Bridgend | Wales | Cadw | Ruin | Free, open access | 4.6 (561) |
| Newcastle (Bridgend) Castle | Bridgend | Wales | Cadw | Ruin | Free, open access | 4.3 (199) |
| Caerphilly Castle | Caerphilly | Wales | Cadw | Partial ruin | Staffed, ticketed | 4.7 (8,511) |
| Cardiff Castle | Cardiff | Wales | Cardiff Council | Intact | Staffed, ticketed | 4.6 (22,719) |
| Castell Coch | Cardiff | Wales | Cadw | Intact | Staffed, ticketed | — |
| Carreg Cennen Castle | Carmarthenshire | Wales | Cadw | Ruin | Staffed, ticketed | 4.7 (2,289) |
| Dinefwr Castle | Carmarthenshire | Wales | Cadw | Ruin | Free, open access | 4.7 (1,859) |
| Dryslwyn Castle | Carmarthenshire | Wales | Cadw | Ruin | Free, open access | 4.7 (660) |
| Kidwelly Castle | Carmarthenshire | Wales | Cadw | Partial ruin | Staffed, ticketed | 4.7 (2,291) |
| Laugharne Castle | Carmarthenshire | Wales | Cadw | Partial ruin | Staffed, ticketed | 4.6 (2,598) |
| Llansteffan Castle | Carmarthenshire | Wales | Cadw | Ruin | Free, open access | 4.7 (971) |
| Aberystwyth Castle | Ceredigion | Wales | Aberystwyth Town Council | Ruin | Free, open access | 4.6 (2,259) |
| Cardigan Castle | Ceredigion | Wales | Cadwgan Building Preservation Trust (Ceredigion CC owns) | Partial ruin | Staffed, ticketed | 4.3 (1,694) |
| Conwy Castle | Conwy | Wales | Cadw | Partial ruin | Staffed, ticketed | 4.7 (21,470) |
| Dolwyddelan Castle | Conwy | Wales | Cadw | Partial ruin | Free, open access | 4.3 (398) |
| Gwydir Castle | Conwy | Wales | Private (Welford family) | Intact | Staffed, ticketed | 4.7 (269) |
| Bodelwyddan Castle | Denbighshire | Wales | Warner Hotels (Bourne Leisure) | Intact | Hotel guests only | 4.5 (2,312) |
| Castell Dinas Bran | Denbighshire | Wales | Denbighshire County Council | Ruin | Free, open access | 4.8 (1,349) |
| Denbigh Castle | Denbighshire | Wales | Cadw | Ruin | Staffed, ticketed | 4.5 (1,142) |
| Rhuddlan Castle | Denbighshire | Wales | Cadw | Ruin | Staffed, ticketed | 4.5 (1,724) |
| Ruthin Castle | Denbighshire | Wales | Ruthin Castle Hotel Ltd | Partial ruin | Hotel guests only | 4.1 (2,362) |
| Caergwrle Castle | Flintshire | Wales | Cadw | Ruin | Free, open access | 4.4 (210) |
| Ewloe Castle | Flintshire | Wales | Cadw | Ruin | Free, open access | 4.6 (872) |
| Flint Castle | Flintshire | Wales | Cadw | Ruin | Free, open access | 4.6 (1,320) |
| Caernarfon Castle | Gwynedd | Wales | Cadw | Partial ruin | Staffed, ticketed | 4.6 (16,170) |
| Castell y Bere | Gwynedd | Wales | Cadw | Ruin | Free, open access | 4.8 (548) |
| Criccieth Castle | Gwynedd | Wales | Cadw | Ruin | Staffed, ticketed | 4.4 (2,806) |
| Dolbadarn Castle | Gwynedd | Wales | Cadw | Partial ruin | Free, open access | 4.7 (1,284) |
| Harlech Castle | Gwynedd | Wales | Cadw | Partial ruin | Staffed, ticketed | 4.6 (8,070) |
| Penrhyn Castle | Gwynedd | Wales | National Trust | Intact | Staffed, ticketed | 4.7 (5,133) |
| Beaumaris Castle | Isle of Anglesey | Wales | Cadw | Partial ruin | Staffed, ticketed | 4.6 (8,582) |
| Cyfarthfa Castle | Merthyr Tydfil | Wales | Merthyr Tydfil County Borough Council | Intact | Grounds only | 4.6 (2,537) |
| Abergavenny Castle & Museum | Monmouthshire | Wales | Monmouthshire County Council (MonLife) | Ruin | Free, open access | 4.5 (849) |
| Caldicot Castle | Monmouthshire | Wales | Monmouthshire County Council (MonLife) | Partial ruin | Staffed, ticketed | 4.6 (2,495) |
| Chepstow Castle | Monmouthshire | Wales | Cadw | Partial ruin | Staffed, ticketed | 4.6 (4,340) |
| Grosmont Castle | Monmouthshire | Wales | Cadw | Ruin | Free, open access | 4.7 (605) |
| Monmouth Castle | Monmouthshire | Wales | Cadw | Ruin | Free, open access | 4 (434) |
| Raglan Castle | Monmouthshire | Wales | Cadw | Partial ruin | Staffed, ticketed | 4.7 (4,199) |
| Skenfrith Castle | Monmouthshire | Wales | Cadw | Ruin | Free, open access | 4.6 (1,038) |
| White Castle | Monmouthshire | Wales | Cadw | Ruin | Free, open access | 4.6 (989) |
| Newport Castle | Newport | Wales | Cadw | Ruin | Grounds only | — |
| Carew Castle & Tidal Mill | Pembrokeshire | Wales | Pembrokeshire Coast National Park Authority | Partial ruin | Staffed, ticketed | 4.7 (3,270) |
| Cilgerran Castle | Pembrokeshire | Wales | Cadw | Partial ruin | Free, open access | 4.4 (1,178) |
| Haverfordwest Castle | Pembrokeshire | Wales | Pembrokeshire County Council | Ruin | Free, open access | — |
| Llawhaden Castle | Pembrokeshire | Wales | Cadw | Ruin | Free, open access | 4.6 (455) |
| Manorbier Castle | Pembrokeshire | Wales | Private (Naper family) | Partial ruin | Staffed, ticketed | 4.5 (1,417) |
| Pembroke Castle | Pembrokeshire | Wales | Pembroke Castle Trust (private charitable trust) | Partial ruin | Staffed, ticketed | 4.7 (8,098) |
| Picton Castle | Pembrokeshire | Wales | Picton Castle Trust (charity) | Intact | Staffed, ticketed | 4.6 (1,419) |
| Roch Castle | Pembrokeshire | Wales | Retreats Group (private) | Intact | Hotel guests only | 4.9 (246) |
| Wiston Castle | Pembrokeshire | Wales | Cadw | Ruin | Free, open access | 4.4 (111) |
| Bronllys Castle | Powys | Wales | Cadw | Partial ruin | Free, open access | 4.4 (241) |
| Craig-y-Nos Castle | Powys | Wales | Private hotel (Craig-y-Nos Castle Hotel) | Intact | Hotel guests only | 4.4 (834) |
| Dolforwyn Castle | Powys | Wales | Cadw | Ruin | Free, open access | 4.6 (320) |
| Hay Castle | Powys | Wales | Hay Castle Trust | Partial ruin | Staffed, ticketed | 4.5 (745) |
| Montgomery Castle | Powys | Wales | Cadw | Ruin | Free, open access | 4.6 (894) |
| Powis Castle | Powys | Wales | National Trust | Intact | Staffed, ticketed | 4.7 (8,226) |
| Tretower Court and Castle | Powys | Wales | Cadw | Partial ruin | Staffed, ticketed | 4.7 (783) |
| Loughor Castle | Swansea | Wales | Cadw | Ruin | Free, open access | 4 (231) |
| Oxwich Castle | Swansea | Wales | Cadw | Partial ruin | Limited tour days | 4.2 (159) |
| Oystermouth Castle | Swansea | Wales | Swansea Council with Friends of Oystermouth Castle | Ruin | Staffed, ticketed | 4.5 (1,201) |
| Swansea Castle | Swansea | Wales | Cadw | Ruin | Free, open access | 4 (1,030) |
| Weobley Castle | Swansea | Wales | Cadw | Partial ruin | Staffed, ticketed | 4.4 (415) |
| Fonmon Castle | Vale of Glamorgan | Wales | Private (Fonmon Castle Estate) | Intact | Staffed, ticketed | 4.7 (1,091) |
| Hensol Castle | Vale of Glamorgan | Wales | Vale Resort (Leekes Group) | Intact | Limited tour days | 4.7 (827) |
| Ogmore Castle | Vale of Glamorgan | Wales | Cadw | Ruin | Free, open access | 4.7 (1,533) |
| Old Beaupre Castle | Vale of Glamorgan | Wales | Cadw | Partial ruin | Free, open access | 4.3 (142) |
| St Donat's Castle | Vale of Glamorgan | Wales | UWC Atlantic College | Intact | Limited tour days | 4.6 (329) |
| St Quentin's Castle (Llanblethian) | Vale of Glamorgan | Wales | Cadw | Ruin | Free, open access | 4.3 (247) |
| Chirk Castle | Wrexham | Wales | National Trust | Intact | Staffed, ticketed | 4.7 (7,076) |