Menhirs de Clendy, Stone alignment near Lake Neuchâtel in Yverdon-les-Bains, Switzerland.

The Menhirs of Clendy are 45 standing stones set in a wooded clearing at the eastern edge of Yverdon-les-Bains, near the southwestern end of Lake Neuchâtel. They form two rows about 50 m long plus three groups south of the rows, and range from 0.45 m to 4.5 m high. Some stones were worked in prehistory into geometric or human-like shapes, occasionally with a marked head.

The menhirs were raised in the 4th millennium BC by inhabitants of the region's lake-dwelling settlements, when the site stood on the shore of Lake Neuchâtel. The rising lake later submerged them, and during the 1st millennium BC the stones gradually fell and were buried under alluvium. They reappeared after the Jura water correction lowered the lake by more than 2 metres; Charles de Sinner published the first description in 1896, and Jacques Henri Gabas excavated the site in 1975, locating the original pits.

The central row runs at an azimuth of 222° from its eastern end, an angle complementary to the golden angle of about 137.57°. Some stones were cut into geometric or human shapes, a few with a marked head, and the forms are compared with decorative patterns in France. The site was also used in the Bronze Age, so not all stones date from the same period.

The stones stand in a wooded clearing at the eastern edge of Yverdon-les-Bains, near the main road to Estavayer-le-Lac, at the south-western end of Lake Neuchâtel. The rows run about 50 m, with further groups to the south. The largest menhirs were re-erected in 1986; the smaller ones are concrete copies, with the originals kept in the Yverdon museum.

The central row points at an azimuth of 222° from its eastern end, the complementary angle of a golden angle (137.57°). The largest stones were re-erected in 1986, but the smallest are concrete copies; the originals are kept in the Yverdon museum.