Courmayeur · Italy

The black glacier

The glacier above this plain does not have the appearance of ice. The Miage carries so much rock down from the Italian side of Mont Blanc that its surface is entirely covered in it, grey and brown and in motion, which is why they call it the black glacier. The stone is also the reason it is still here. The layer of debris shades the ice beneath and slows the melting, so that the Miage descends to about 1,700 metres, lower than almost any glacier in the Alps. The flat ground on which you stand was a lake, dammed by the moraine the glacier pushed across the valley. A small lake still forms at the snout, fills over a season or two, and empties without warning.

Go deeper

Why is it covered in stone?

Because of what stands above it. The walls that feed the Miage are steep and shed rock constantly, and everything that lands on the ice rides down with it. A glacier under gentler slopes stays white.

Is it shrinking?

Yes, like every glacier in the Alps, though the debris cover slows it down. The Miage has lost more thickness than length: it is going down rather than back, which is harder to see from here.

Is the lake dangerous?

It has emptied suddenly before, which is why it is watched. Stay off the moraine walls around it: they are unstable ice under unstable stone and they collapse without warning.

Where it is

Lago di Combal, Val Veny, 11013 Courmayeur · 45.77444, 6.86022 · Open in Maps

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