I have just added this to the map of places to fly your drone at Drone Scene:
Land owner permission not required.
Just behind the NT boundary of Ashdown House. You can park in the free car park and walk down the path through the woods. You then cross 2 stiles and you are there.
Alfred's Castle is a small Iron Age hill fort, situated 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.
The originator declared that this location was not inside a Flight Restriction Zone at the time of being flown on 14/11/2021. It remains the responsibility of any pilot to check for any changes before flying at the same location.