Lake Oô is located on the town of the same name (which means "high mountain" in Occitan gascon), near Bagneres-de-Luchon, in Haute-Garonne.
Of glacial origin, it is now considered an artificial lake since the construction of a dam dedicated to power a hydroelectric plant in 1921.
Covering an area of 42 hectares, with a maximum depth of 67 m, the lake punctuates the vast summer pasture (grazing area) of the town, at an altitude of 1507 m.
Known crossword lovers, the lake is especially popular with hikers who can reach it by following the route of the GR10 (whose route crosses the chain of the Pyrenees, connecting the Mediterranean Sea to the Atlantic Ocean). The trail then passes the Spanish border.
At the lake level, which consists of a postcard-like landscape, there is a 275-meter high waterfall, and a refuge has been built. The whole lake and its surroundings is classified Natura 2000 because of the richness of its biodiversity.
Information on +33 5 61 79 21 21.