The Tower of London, officially known as His Majesty's Royal Palace and Fortress of the Tower of London, is a historic castle located on the north bank of the River Thames in central London. Founded in 1066 as part of the Norman Conquest, it has served variously as a royal palace, prison, treasury, and home of the Crown Jewels of England. The White Tower, built by William the Conqueror in 1078, gives the entire castle its name and was a symbol of oppression for the city's inhabitants. The Tower's layout, established by the late 13th century, remains largely the same today, despite later modifications. The Tower has played a prominent role in English history, with control of it seen as crucial to controlling the country. It has been besieged several times and has witnessed the executions of 12 men for espionage during the World Wars. Today, the Tower of London is one of the country's most popular tourist attractions, cared for by the charity Historic Royal Palaces and protected as a World Heritage Site. Visitors can explore the White Tower, the innermost ward, the inner ward, and the outer ward, each with its own unique history and architectural features.