Castles are fortified residences.
Understand
[edit]True Castles (those built for defensive purposes) in the United Kingdom were constructed from the start of the Norman Conquest (1066) onward, until the early 17th century when developments in military technology rendered them less effective from a military standpoint. Sometimes the castles were built on or near the basis of early pre-Norman fortifications. Whilst there are true castles in Scotland (notably Edinburgh and Stirling), there are also a number of tower-houses (effectively fortified residences).
Destinations
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Dates of Sieges are in brackets
England
[edit]Royal Castles
[edit]1 Tower of London (1460 
), St Katharine's & Wapping, City of London, EC3N 4AB. Founded by William the Conqueror in 1066, enlarged and modified by successive sovereigns. The Tower is today one of the world's most famous and spectacular fortresses and a UNESCO World Heritage Site. Its 900-year history includes use as: a royal palace and fortress, prison and place of execution, mint, arsenal, menagerie and jewel house. The Tower contains enough buildings and exhibits to keep a family busy for a full day, with plenty of both warlike and domestic contents. Beefeaters, who are all retired sergeant majors from the British Army, provide guided tours for free as well as ceremonial security. See history come alive – go to the Ceremony of the Keys at the Tower of London. This ceremony, the locking up of the Tower, has been performed every night at 10PM for 800 years. Tickets for the ceremony are free but MUST be prearranged. 
2 Windsor Castle, Windsor, SL4 1NJ. It was built by William the Conqueror following the Norman invasion in the 11th century, and has been used by the British royal family since the reign of King Henry I. It is the largest inhabited castle in the world and was used by Queen Elizabeth as her primary weekend residence, though the state rooms are open to the public when not in use for state ceremonies.
Complete Castles
[edit]3 Alnwick Castle, Alnwick, NE66 1NQ. The "poison garden" tour is entertaining. Seeing the castle might be a thrill for people who are fans of the Harry Potter films, Rowan Atkinson's "Black Adder", Transformer 5, or Downtown Abbey (it was used as "Brancaster Castle" in two Christmas specials. Walking tours are included in the prices (historical or film locations).
4 Clifford's Tower (York Castle), York. Originally the Keep of a Motte and Bailey Castle, with a new viewing platform.
5 Colchester Castle, Colchester, [email protected]. The largest Norman keep in Britain, built on the foundations of the Roman temple to Claudius. The city centre on one side and landscaped gardens on the other. The museum covers the extensive history of Britain's oldest recorded town, from pre-Roman times, Boudicca's rebellion, the Norman invasion, medieval witch hunts, the civil war and up to the present day.
6 Dover Castle, Dover, CT16 1HU. Known as the "Key to England", the castle has 2,000 years of history contained within its walls, including a Roman lighthouse, a Saxon church and a Norman keep. Below ground, a series of casements and tunnels have been dug into the chalk. From these tunnels, Operation Dynamo (the Dunkirk evacuation) was planned. National Trust.
7 Dunster Castle, Minehead, TA24 6SL. Built on a hill overlooking Dunster Village. Besieged by the Parliamentarians during the English Civil War in 1645. National Trust.
8 Durham Castle, Durham. Built by the Norman's, much altered in the 19th century and is part of a World Heritage Site
9 Pendennis Castle, Falmouth. One of the finest surviving examples of a coast fortress in England. Successive remains chart developments in military engineering and weapons technology and the organisation of coast defence from the Tudor period until the Second World War. Cornish Heritage Trust and English Heritage members: Free.
10 Lancaster Castle, Lancaster. This is the gaunt castle of the Duke of Lancaster, i.e. the Queen. The oldest parts are 11th century though with much Victorian addition. Visit the interior only by guided tour: this takes in the state rooms, court rooms, and prison cells. Free Entry, Adult tour £8, concession & child tour £6.50.
11 Leeds Castle, Maidstone, ME17 1PL (Near Maidstone Kent [not in Yourshire].). Described by Lord Cornway as "the loveliest castle in the world".
12 Warwick Castle, Warwick, CV34 6AH. Originally built by William the Conqueror 1068 as a wooden motte and bailey castle and converted into stone in the 12th century.
Ruined Castles
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13 Bodiam Castle, Robertsbridge, TN32 5UA. Well preserved exterior that's been used in many famous films, including Monty Python's search for the Holy Grail. National Trust.
14 Corfe Castle (1643 1645), Corfe Castle, BH20 5EZ. Besieged by Parliamentarians unsuccessful in 1643 and again in 1645 successfully before they slighted it. National Trust.
Northern Ireland
[edit]15 Carrickfergus Castle, Carrickfergus BT38 7BG.
Scotland
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16 Edinburgh Castle, Edinburgh, EH1 2NG. Edinburgh grew up around Edinburgh Castle that is perched atop its volcanic crag. It still has a military garrison and the regimental museums of Royal Scots and Royal Scots Dragoon Guards. the Edinburgh Military Tatoo is held in August.
17 Stirling Castle, Stirling, FK8 1EJ. Pocket-sized edition of Edinburgh Castle, similarly poised on a crag with steep cliffs on three sides and tail of glacial rubble. It dates back at least to the 12th century, with most of its interior from the 15th and 16th when James IV, V and VI developed it as a royal residence in Renaissance style. Became an army base in 1800 and remains the HQ of the Argyll and Sutherland Highlanders with their regimental museum, though nowadays quartered in Edinburgh.
18 Eilean Donan Castle, Dornie. The original Donan was a 7th century saint and martyr, and there's been some kind of settlement here since ancient times. The main incarnation of the castle was from the 13th century, a redoubt of Clan Mackenzie, and was much bashed-about but survived until the 18th. After the 1715 Jacobite rebellion failed a further uprising was attempted in 1719 but never got started, but some Spanish troops and other rebels holed up in the castle. Three navy ships arrived to negotiate their surrender, but the landing boat was fired upon while under flag of truce. Big mistake: when the ships departed three days later, the castle was rubble and the surviving rebels were in shackles below deck. It remained ruined until the 20th century when it was restored as an "show" castle, and joined to the mainland by the stone bridge. It opened to the public in 1955 and has been a popular film-location ever since.
19 Crathes Castle, near Banchory, Aberdeenshire. Attractive 16th-century castle with turreted tower, thick walls and ivy growing up the cream walls. Extensive garden with carved yew hedges and colourful borders. There are several other castles in Aberdeenshire, including the Royal Family's personal castle of Balmoral, near Ballater, which you may be able to visit April - July.
20 Dun Carloway, Chàrlabhaigh (Carloway), Lewis HS2 9AZ. A broch or round tower built around 200 BC and inhabited until 1000 AD; it was a hideout of cattle thieves in the 17th century. Parts of the broch walls still reach their original height of 9 m.
Wales
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21 Beaumaris Castle, Beaumaris LL58 8AP.
22 Caernarfon Castle (Carnarvon Castle - Welsh: Castell Caernarfon), Caernarfon, LL55 2AY. An impressive work began in 1283 by England's King Edward I as his planned seat of power in his attempt to subjugate Wales. Like Beaumaris, this castle was quite functional, although never 100% completed. Notable use of this castle has included the investiture of a Princes of Wales on at least two occasions.
23 Harlech Castle (Welsh: Castell Harlech 1404 1409 1468 1647), Harlech LL46 2YH. In 1404 the castle fell to the Welsh prince Owain Glyndŵr. In 1409 Harlech besieged by forces of Harry of Monmouth – later Henry V fell. In Wars of the Roses this Lancastrian-held castle was surrounded and captured by the Yorkists in 1468. In 1647 it was the last Royalist castle to fall to the Parliamentarians
24 Pembroke Castle (1648), Pembroke, SA71 4LE. Situated on the hill overlooking the High St., Pembroke Castle has breathtaking views of the town. The castle itself is interesting, its towers and walls are intact. It's even the birthplace of King Henry VII - depicted in his tower. Oliver Cromwell besieged Pembroke on 24 May 1648 and took the castle after a seven weeks. £8.50.
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