The Tower of London is a historic castle located on the north bank of the River Thames in central London. Built in the 11th century by William the Conqueror, it has served various purposes, including a royal palace, fortress, and prison. The tower is famous for housing the Crown Jewels and has been a symbol of British history for centuries. The Tower consists of several buildings set within two concentric rings of defensive walls. It is a UNESCO World Heritage Site and attracts millions of visitors each year. The Yeoman Warders, also known as Beefeaters, provide guided tours, sharing stories of the tower's rich and often dark history.