Warwick Castle is an earthwork motte and bailey fortress, founded by William the Conqueror in 1068. In the mid 13th century, John de Plessis founded the stone castle, when crowning the motte with a shell keep. The unique towers, remarkable gatehouse and barbican, give strong defence to the enclosure and the weaker Great Hall is protected by the river cliff. The motte and the Ghost Tower stand at one end, with the Gatehouse, Guy's Tower and Caesar's Tower at the other. In-between, facing the town, is part of Richard of Gloucester's unfinished great keep, with only two of the four towers remaining. 5 miles north is Kenilworth Castle and 7 miles north-west is Baddesley Clinton Hall.