Lago Nero, Alpine lake in Pistoia Province, Italy

Lago Nero is a mountain lake in the Tuscan Apennines, sitting at around 1,730 meters (5,675 ft) above sea level in Pistoia Province. It occupies a natural hollow surrounded by steep wooded slopes and exposed rock faces that drop close to the water.

The lake formed at the end of the last ice age, when glaciers carved a hollow into the rock and left behind the basin that eventually filled with meltwater. The surrounding landscape still shows the rounded, scraped contours left by that slow movement of ice.

The name Lago Nero, "Black Lake", comes from the dark reflection the water gives off, and the lake drains into the Sestaione torrent, the main tributary of the Lima, itself the main tributary of the Serchio. Walkers on the white-red CAI trail no. 104 from the Abetone botanical garden pass the CAI Rifugio Lago Nero beside the water, which keeps a bivouac open at all times.

The lake is reached only on foot via hiking trails, so sturdy footwear is a good idea. The terrain is steep and can be slippery after rain, and mountain weather changes fast, so it is worth checking conditions before heading out.

Despite its small size, the lake can reach several meters in depth at certain points, which contributes to the dark look of the water from above. This makes it one of the few genuinely deep glacial lakes in the Tuscan Apennines.