Piton des Neiges, Dormant volcano in Réunion, France.

Piton des Neiges is a dormant complex volcano whose summit, at 3,070 m, is the highest point on Réunion and in the Indian Ocean. Its upper slopes are bare grey and brown basalt with jagged ridges and deep gullies, while green vegetation covers the lower flanks above the plains.

Piton des Neiges grew from a shield volcano whose first lavas pierced the ocean floor five to seven million years ago; the oldest dated land rock is 2.1 million years old, and the island probably emerged about three million years ago. A second phase, from roughly 450,000 to 340,000 years ago until the last eruptions 29,000 to 12,000 years ago, built the present summit and the cirques. The volcano has been inactive for more than 12,000 years.

The name "Snow Peak" likely dates from a snowfall recorded in 1735; snow now falls on average only one day every three years, and the summit is rarely seen white. The summit marks the boundary between the communes of Cilaos and Salazie. Barau's petrels, seabirds endemic to Réunion, nest in burrows under the summit rocks from late August until the young fledge in April–May.

Several hiking trails lead to the summit with varying difficulty levels and distances. Many hikers use the mountain shelter Caverne Dufour as a rest point before the final push.

Erosion carved three deep valleys with nearly vertical cliffs at the volcano's base, known as the cirques. This geological feature kept these valleys isolated for centuries and shaped how people settled and lived there.