The generally level summit area of Gateholm, a half-tide islet, roughly 500m by up to 100m, shows the earthwork remains of a settlement, comprising about 110 rectangular structures. The structures are organised into courts and rows and access to the isle appears to have been controlled by a rampart and gate at its north-western tip, facing the mainland, a further stretch of bank occurs along the northern edge of the summit area. The gateway appears to have been a mortared-stone structure. Limited explorations of structures in the interior (Cantrill; Archaeologia Cambrensis, 1910; Lethbridge & David; Archaeologia Cambrensis, 1930), produced a range of finds, including nails & burnt stone: the best known structure, or compartment, was about 6.0m north-south by 3.0-3.6m internally, defined by a turf wall about 1.0m thick with an internal drystone revetment & featured a hearth & two postholes thought to represent roof support. Overall, the finds point to late-Roman to early medieval occupation, with some earlier material, whilst possible thirteenth century pottery may hint at a dating context for the mortared gate structure.

RCAHMW, 17 February 2009

Reappraisal of the islet and its archaeological remains was carried out by Oliver Davis from LiDAR in 2011 (see Davis, O. 2011. A LiDAR survey of Skokholm Island, Gateholm Islet and the Marloes Peninsular, Pembrokeshire, Archaeologia Cambrensis 160, 115-132). Excavations were carried out by Time Team in 2013.

Updated by T. Driver, RCAHMW, Nov 2017