The Grotte de Cottier is an archaeological site located in the hamlet of Cottier 2 km northwest of the commune of Retournac, Haute-Loire, which has yielded Magdalenian remains. The site is now closed to the public.

The various interventions made it possible to discover more than four thousand archaeological remains: reindeer wood spears, bone needles, and pierced teeth used as pendants. These discoveries are attributed to the Lower Magdalenian and therefore date from 15,000 to 18,000 BC. A dating made before 1976 on a calcined bone of level 2 gave 18,550 years ± 550 years AD.

Archaeologists have also discovered animal remains in the cave: cave cuon, collared lemming, snow vole, reindeer, chamois, and ibex. This assemblage of fauna indicates a cold climate.