Alignements de Kerzérho is an alley of menhirs, measuring 50 meters in width and has 10 rows. It stretches between Erdeven and Plouharnel (in Brittany) and is more than 2 km long. The highest concentration of menhirs is near the town of Erdeven.
The reported numbers of menhirs in this grouping vary considerably from one source to another. The well-preserved drawing of the 1832 shows that there had to be several thousand menhirs here. In 1884, local native Felix Gaillard counted over 1,100 menhirs standing and over 5,000 menhirs lying down on the ground. But even then the menhirs were used (like stones from the ruins of many castles elsewhere in Europe) as cheap building materials, as garden ornaments and for the construction of stone fences. Today there are only about 200 standing menhirs in the main group! Scattered groups of menhirs in the surrounding forests - the Alignements de Kerjean, the Alignements de la Table du Sacrifice and others - are part of these rows.