Clifford's Tower is the magnificent surviving centerpiece of York Castle, a medieval fortress that has dominated the city's skyline since 1068 when William the Conqueror built it to subdue northern rebellions. The distinctive stone tower, rebuilt by Henry III in the 13th century after earlier fires, rises majestically above York's historic landscape and takes its name from a tragic historical incident involving Roger de Clifford's execution. The tower witnessed one of the darkest chapters in English history when York's Jewish community sought refuge there during a 1190 massacre, marking it as a significant site in medieval social history. Now managed by English Heritage, the tower features a modern roof deck providing panoramic views across York's medieval rooftops and the famous Minster, while exhibits interpret centuries of history from Norman conquest to Civil War.