Lac de Bethmale, lake in France

Lac de Bethmale is a small artificial pond at 1,074 metres in the Ariège Pyrenees, on the GR 10 long-distance path above the Bethmale valley. It lies in a karst depression: water seeps through Palaeozoic limestone between the pond and Mont Valier and resurges through springs, or griffons, visible in the pond. Impermeable granitoid rocks near the outlet act as a dam. The pond is stocked with fish and has facilities for visitors with reduced mobility.

The name Bethmale comes from the Gascon language, combining 'beth' meaning beautiful and 'malh' referring to rocky mountain terrain. This artificial reservoir was created later to serve the water needs of the mountain community.

The name Bethmale likely derives from Gascon 'beth' (beautiful) and 'malh' (mountain flank), though a reading from 'vath' (valley) and 'mala' (bad) has also been proposed. The pond is regularly stocked, and anglers fish it with a day card; the site lies on the GR 10 long-distance footpath, so hikers pass the shore between the Bethmale valley villages and the col de la Core.

Wear sturdy footwear since paths around the water can be uneven and slippery in places. The best time to visit is from May through October when weather is stable and all facilities are fully accessible.

Lac de Bethmale is fed by karst springs: water sinks into Palaeozoic limestone between the lake and Mont Valier, travels through an underground network marked by sinkholes and stream losses, then rises through griffons visible in the lake itself. Impermeable granitoid rocks near the spillway dam this reservoir. Speleologists think the network may reach over a kilometre deep.