Lligwy is a Neolithic megalithic tomb chamber, comprising eight variously shaped stones supporting a massive capstone, 5.9m by 5.2m and 1.1m thick. It is constructed over a natural fissure in the rock so that the chamber had a height of about 2.0m. There is no trace of the original cairn, although over the centuries soil has crept up around the stones. The chamber was excavated in 1909, when two layers of deposits were recorded, separated by a layer of paving. The deposits contained unburnt bone, human and animal, pot sherds and some flints and the upper deposit was covered by a layer of limpet shells. Between fifteen and thirty individuals were represented in the tomb chamber. Some of the pottery appears to be Bronze Age and at least one of the layers may represent the re-use of the tomb.
Sources: National Archaeological Record SH58NW1; Baynes in Archaeologia Cambrensis 9 (1909), 217-31; RCAHMW Anglesey Inventory (1937), 133; Lynch 'Prehistoric Anglesey' (1970), 52-5.
RCAHMW, 09 June 2008.