Around 150 Jews died inside York Castle, the majority committing mass suicide to avoid being killed by a mob. York Castle: York Castle is a fortified complex in the city of York, England. It consists of a sequence of castles, prisons, law courts and other buildings, which were built over the last nine centuries on the north-west side of the River Foss. The now ruined keep of the medieval Norman castle is commonly referred to as Clifford's Tower. Built originally on the orders of William the Conqueror to dominate the former Viking city of Jórvík, the castle suffered a tumultuous early history before developing into a major fortification with extensive water defences. After a major explosion in 1684 rendered the remaining military defences uninhabitable, York Castle continued to be used as a jail and prison until 1929. March 16, 1190. Wiki link