The ruins of St Mary's Abbey date from 1270 to 1294. The ruined Gatehall was its main entrance, providing access from the abbey to the river. The adjacent Hospitium dates from the 14th century, although the timber-framed upper storey is a much-restored survivor from the 15th century, used as the abbey guesthouse. St Mary's Lodge was built in about 1470 to provide VIP accommodation.