Kenilworth Castle is a castle located in Kenilworth, Warwickshire, England. The medieval castle is known for its extensive water defences, and the great siege by the future Edward I in 1266, plus the ruins of the ornate Great Hall built by John of Gaunt. Its later history includes the visit of Elizabeth I (it still boasts Tudor buildings and gardens) and the dramatic slighting by Cromwell’s troops, leaving an open side to the fine Norman keep.