From the Wiltshire County Council website:
"Castle Ditches, so called by the 16th century, to the south east of the village, is an Iron Age multivallate hill fort of 24.5 acres.
The ramparts are still up to ten metres high, and there is evidence of an inner ditch. A substantial hill fort such as this would indicate a reasonable sized settlement,
both in the fort itself and probably also of people in the surrounding area, who would use the hill fort in troubled times.

"Mixed farming would have been practised in small rectangular fields, with a wide range of cereals grown.
Livestock was mainly sheep, goats and oxen, with pigs in the wooded river valleys. Doubtless this way of life remained little changed during the Roman period:
although the hill fort would have fallen into disuse shortly after 43 AD, as this area came under Roman control at an early stage of the invasion."

Sadly, there is no public access....