The enrosadira — the Ladin word for the alpenglow phenomenon particular to the Dolomites — is one of the most astonishing spectacles in the Alps. In the twenty minutes around sunrise and sunset, the pale dolomia rock shifts through a sequence of colours: first golden yellow, then deep orange, then a vivid rose-red that seems to come from inside the rock rather than reflected off it. The colours are most intense on the largest vertical rock faces — the Langkofel towers above Alpe di Siusi, the Sella walls above Val Gardena, the Marmolada from Arabba — and they happen fast: you have perhaps five minutes of the full red before the light changes.
The best places to see it depend on which side of the mountains you're on. For dawn: stand in the valley below a west-facing wall — the Tofane seen from Cortina, the Langkofel from the Alpe di Siusi. For sunset: find an east-facing viewpoint — the terrace of any rifugio above 2,000 metres looking toward the Pale di San Martino or the Tre Cime. The phenomenon occurs year-round, but the clearest light tends to be in September and October, after the summer haze has gone.