Cerro Tronador

Tronador means the thunderer, and the name comes from the sound of ice breaking from the hanging glaciers on the mountain's walls and falling hundreds of metres, a boom that carries down the valley on warm afternoons. The peak reaches about 3,478 metres, the highest in the Nahuel Huapi range, and sits astride the border with Chile. The road from Bariloche runs along Lago Mascardi and up the Manso valley to Pampa Linda, then to the Ventisquero Negro, the black glacier, whose ice is dark with rock debris and which calves into a grey meltwater lagoon. A short walk from the road end reaches the Garganta del Diablo amphitheatre, where waterfalls pour off the cliffs from the ice above.

What you actually see

• The Ventisquero Negro - the debris-blackened glacier and its meltwater lagoon.
• The Garganta del Diablo - the rock amphitheatre ringed by falling water.
• The hanging glaciers - ice cliffs that crack and thunder in the afternoon.
• The Manso valley road - the drive through forest along Lago Mascardi.

When to go

December to March, when the road is open; it closes with snow for much of the rest of the year. Afternoons are best for hearing ice fall, but the access road runs one way on a strict timetable, so departure times must be planned.

Honest expectations

The final road is narrow gravel with fixed uphill and downhill hours, and missing the window means waiting hours. The black glacier has retreated dramatically and looks like a dirty ice mass rather than a postcard glacier. Weather often hides the summit entirely.

Nearby

Pampa Linda has lodging and trailheads; Bariloche lies northeast.