This is a lovely site and very accessible.
The only reference to the place that I can find is by Stanhope White, who places it in the Iron Age but the vibe I get is of a henge albeit an angular henge.
What you’ve got is a square-ish enclosure with rounded corners surrounded by a rounded ditch the a bank with one possibly two entrances.
The dimensions are roughly 55 metres from corner to corner of the enclosure, an 8 metre wide ditch and an 8 metre wide bank with no external ditch.
The setting is a faily flat plain of fertile farmland, the are barrows in the vacinity and a set of double dykes.
I would love to know more about this site.
Conclusion – Well worth a visit, whatever it is.
Check out the multimap aerial view.