Cronk Mooar was a medieval burial mound which was excavated fully before it was lost to coastal erosion in the mid-20th century. Cronk Mooar was surveyed and archaeologically removed by Mr (later Professor) I. Bowen at the request of the Air Ministry in 1939. Investigation was curtailed at the outbreak of war but was resumed by Dr G. Bersu in 1945.


The 1939 excavation found that the mutilated, sandy mound appeared to have been 10-11 metres in diameter and about 3.0 metres high before its systematic removal down to the probable old turf-line. No trace of structures were found except for the remains of a wooden beam which protruded from an infilled central pit (not investigated until 1945). The mound material revealed some flints, including artefacts, burnt clay, charcoal, fragments of iron slag, burnt bone and evidently a number of nails which were erroneously considered (as proved in 1945) to belong to a ship burial.


In 1945 the second excavation investigated the untouched soil beneath the removed mound; the humus above this level contained flints, iron slag, animal bone, possibly daub and some badly eroded prehistoric pottery. The central pit and decayed wooden beam, located by Bowen, was further investigated. The sides of the pit were lined with wooden planks forming a box or coffin which Wilson later interpreted as a probable 'Kammergrab' (Scandanavian timber-lined burial chamber). This feature contained at its base an extended Viking male burial, much decayed, together with a Celtic ring-headed pin, wooden-handled iron knife with leather sheath, bronze strap-distributor, a bronze strap-end made from a Celtic (probably Irish) book clasp and an iron sword (broken in three places) with an ornamented scabbard. Fragments of textiles were identified as the remains of a woollen cloak which had been worn by the deceased.