The Lago Nero is situated on a step, in the highest area of the Nure torrent basin, close to the watershed with Val Ceno. The basin opens on a small “cirque”, along the western slope of Monte Bue, 1540 metres above sea level.
The form of the lake is oval, it is abou 200 m long and 80 m wide, a maximum depth of 2.5 m. Its banks are covered in gravel, crushed stones and rubble, with bushes and shrubs here and there.
Its water balance is almost always even thanks to the frequent rains. Since the basin stands at a high altitude, it is frozen from November to April.