Caerleon Castle is an 11th century earthwork motte and bailey fortress, founded by Caradoc ap Gryffyd, Lord of Caerleon. In 1270, Gilbert de Clare founded the stone castle and crowned the steep motte with a high keep. The motte was encased by a wide ditch and flanked by a twin-towered gateway, which guarded a flight of steps that gave access to the keep. The inner bailey retains part of its curtain wall and besides the River Usk are the remains of the Hanbury Tower, a round flanking tower. 3 miles south-west is Newport Castle and 8 miles north is Usk Castle.