Square earthwork enclosure, nestled between two outcrops overlooking the southern approaches to Grassholm Island. The enclosure measures 10m square, and is defined by low earthwork banks measuring approx. 1.5m wide. There is a probable entrance on the north side. The enclosure stands in the grassy area of Grassholm, defined by a deeply perforated turf 'mat' of former puffin burrows. A site visit during 2019 identified an outcrop-top cairn (NPRN 424559) overlooking the enclosure on the south side, and a rectangular platform (NPRN 424560) below and to the east of the enclosure.
Recorded by T. Driver, L. Barker, D. Hunt and P. Robson for the CHERISH Project, 21-22nd October 2019.
