I have just added this to the map of places to fly your drone at Drone Scene:
Land owner permission not required.
Parking & TOAL: 51.163305, -1.928006
Yarnbury Castle (ancient hillfort) is just north of the A303 dual carriageway. There is no parking in the close vacinity. The nearest place that I found was a lay-by on the east bound A303 about 800m east of the hillfort.
Yarnbury Castle is the site of a multiphase, multivallate Iron Age hillfort near the village of Steeple Langford, Wiltshire, England. It is dated from 300BC. The site covers an area of 28.5 acres, and was extensively surveyed and investigated by the Royal Commission on the Historical Monuments of England in 1991, with finds of Iron Age and Romano-British pottery, Iron Age and Roman coins, and burials of human remains.
The originator declared that this location was not inside a Flight Restriction Zone at the time of being flown on 26/02/2023. It remains the responsibility of any pilot to check for any changes before flying at the same location.