Plaine des Sables, Volcanic plateau in Saint-Joseph and Sainte-Rose, Réunion, France

Plaine des Sables is a bare volcanic plateau in the highlands of Reunion Island, located between the communes of Saint-Joseph and Sainte-Rose. The ground is made up of dark basalt rock, loose stones, and fine volcanic sand that gives the terrain an open, flat appearance at high elevation.

The plain formed through a series of collapses and fillings between 65,000 and 30,000 years ago, not by lava flows building up the plateau. After a first collapse, the Plateau des Basaltes remained as a remnant of successive fillings that later collapsed again. A small cone that erupted at the top of the rampart 1,000 to 5,000 years ago sent out a flow that formed the Pas des Sables bank.

The plain sits along the main route that hikers and drivers take when heading toward the Piton de la Fournaise volcano. The stark contrast between its dark, bare ground and the green forests found lower on the island makes it a natural stopping point where people pause to look around.

The plateau sits above 6,500 feet (2,000 m) and is fully exposed to wind and sun, so warm layers and water are necessary. Starting the visit in the morning gives better visibility and helps avoid the clouds and rain that often roll in during the afternoon.

Patches of red and golden mineral deposits, caused by oxidized iron, appear across the dark basalt of the plain. These colors are especially visible in direct sunlight and give parts of the ground a look that many visitors compare to photos of Mars.