The Tower of London is a historic castle located in central London in the Borough of Tower Hamlets. It is located on the north bank of the river Thames. The Tower was founded in 1066 during the Norman Conquest. The old keep, called the White Tower, was built in 1078 by William the Conqueror and still stands today. Throughout its history, the castle has served as a royal residence as well as a prison, and many executions were held on Tower Hill to the north of the Tower, including Anne Boleyn. It has been through several periods of expansion and became a complex of several buildings set within a moat and defensive walls. It has been the site of several significant historical events, such as the disappearance of the imprisoned “Princes in the Tower” in the late fifteenth century and the imprisonment of Elizabeth I during the reign of Mary I in the sixteenth century. Famous people imprisoned in the Tower include Lady Jane Grey, Guy Fawkes, Thomas More, Thomas Cromwell, and Sir Walter Raleigh. The Crown Jewels are also traditionally kept in the Tower. Today, the Tower is a popular tourist attraction and UNESCO World Heritage Site.