The Tower of London is a UNESCO World Heritage Site established in 1066 during the Norman Conquest, serving as a royal palace, fortress, prison, and treasury throughout its millennium of history. The central White Tower, built around 1078 with limestone from Caen in Normandy, exemplifies medieval military architecture and remains a symbol of royal power since William the Conqueror. Today the fortress houses the Crown Jewels, showcasing the opulence of the British monarchy, and the Royal Armouries, providing insights into the nation's military heritage. Located on the north bank of the River Thames in central London, it remains one of Britain's most iconic monuments and a major reference point for the history of medieval fortifications.