Unlike many Norman fortifications there is no motte at Caerau, only a bank and outer ditch. The bank would have had a wooden palisade atop to provide extra protection.
There is a gap in the bank on the south west side, which is probably where the main entrance would have stood, protected by a wooden tower.
Nearby is the 13th century church of St Mary's, whose graveyard may lie on the site of the castle bailey, or outer enclosure. Much of the site has been overgrown with vegetation.