Just the ruined base of a great tower remains at Pendragon Castle, which according to legend is the place where Uther Pendragon, King Arthur's father, died. The castle was built next to the River Eden in the Vale of Mallerstang in the late 12th century, probably by Hugh de Morville.

Like the nearby castles of Appleby and Brough, Pendragon came into the possession of the Clifford family. It was abandoned after a raiding Scottish army set fire to the castle in 1341, but was rebuilt in 1360. It was left in ruins by another fire in 1541, but was restored in the mid 17th century by Lady Anne Clifford. The castle gradually fell back into ruin after her death.