We stumbled on this small charming enclosure while ambling around the New Forest. It's not very big, popular with local bovine herds, probably no more than about 20-25m in diameter and the banks no more than 1.5m high (mostly on the southern side). I imagine in the winter months it's probably very boggy around here and the northern and eastern sides are bounded by the beginnings of the Beaulieu River which acts as a natural defence. Pastscape describes the earthwork as a Bronze Age enclosure or early Iron Age univalate Fort. I'd go for the former as the earthworks don't seem like they were ever defensive and more about preserving a bit of dry ground in a very flat area. There are also a number of (presumably) Bronze Age barrows nearby which might support that.