From the Domaine departmental du Morbihan leaflet “er lannic”
“In 1866 De Closmadeuc discovered the prehistoric site of Er Lannic. He made a rapid description of the northern hemicycle composed of 60 blocks of stone and it was only in 1872 that thanks to a very low tide that he discovered the second semi-circle, 4 or 5 menhirs which had been submerged were still upright....The site was restored by Le Rouzic and St Just Pequart between 1923 and 1926. An excavation revealed chests, fireplaces and lithic material (flint stones, poliching stones, strikers, polished axes and grinders) and about 800kg of pottery.”