Carnac (kärnäkˈ) [key], town (1993 est. pop. 4,322), Morbihan dept., NW France, in Brittany, at the foot of the Quiberon peninsula. It is the site of remarkable megalithic monuments, particularly the menhir. The menhirs, formerly ascribed to the druids, extend along the coast in 11 parallel rows, 1,100 yd (1,006 m) long; some are 20 ft (6.1 m) high. The sea resort of Carnac-Plage is nearby.