Location: Windsor, Berkshire, England Date completed: 11th Century (subsequently extensively rebuilt and modified) Designer/Builder: Originally commissioned by William the Conqueror, frequent rebuilt by succeeding monarchs. Function: Stronghold and royal residence

Even today, Windsor Castle dominates the skyline - you can see it clearly from the motorway and, on a clear day, even from the top of the London Eye, 25 miles (40 km) away. That was what it was meant to do when it was originally built after the Norman Conquest, occupying a strategic position overlooking the River Thames and routes out of London. Originally a wood and earth motte and bailey structure, Windsor Castle has been strengthened, enlarged and refurbished ever since. Henry I (reigned 1100-1135) used it as a residence, as did successive monarchs, making it the longest continuously occupied palace in Europe. Henry III (r. 1216-1272) remodelled the state apartments within its walls and added five circular towers, while Edward III (r. 1327-1377) comprehensively rebuilt the Castle, adding the College of St George, new Royal apartments, the Great Hall and the Royal Chapel. The Parliamentarians occupied the Castle during the Civil War and used it as a prison. Charles I was buried in the Chapel of St George after he was executed in 1649. After the Restoration, Charles II (r. 1660-1685) made the Castle a royal residence again, commissioning a range of elaborate Baroque interiors. George III (r. 1760-1820) and George IV (r. 1820-30) rebuilt the Castle at huge expense producing the State Apartments much as we see them today. During World War II (1939-1945) the royal Princesses Elizabeth and Margaret lived full time at Windsor Castle as a refuge from the Blitz. It is today the preferred weekend home of Queen Elizabeth II.

On the morning of Friday 20th November 1992 a fire started in Windsor Castle, when a spotlight ignited a curtain in the Queen's Private Chapel. Despite the rapid response of the in-house and local fire fighters (eventually numbering several hundred) the fire spread rapidly and caused extensive damage to the fabric of the Castle. Fortunately no one was killed or seriously injured and volunteers managed to save much valuable art works and furniture (including a 150 ft (46 m) long table!). However, it took several years to repair the damage, at a cost of £36.5 million.