Alfred's Castle is a small Iron Age hill fort, situated at grid reference SU277822, behind Ashdown Park in the civil parish of Ashbury in Oxfordshire (formerly Berkshire). It lies 2–3 km south of the Ridgeway and is protected as a Scheduled Ancient Monument. Excavations were carried out at Alfred's Castle from 1998 to 2000 by archaeologists from Oxford University. A final analysis was published in 2014.