The Piton de la Fournaise volcano (Furnace Peak) is still active and erupts more or less annually. The whole area around the central crater is a lunar landscape of cinder and ash, devoid of vegetation, in deep shades of reddy-brown and black. The 13 km hike to the volcano rim is a relatively easy walk but you must go prepared. Alternatively, the round trip walk to the Formica Lion, a smaller cone, is considerably shorter - about 90 minutes.
To hike up to the volcano is best to overnight at Bourg Murat, on La Plaine des Cafres. This part of Reunion is characterized by Alpine-style high altitude pastures and moorland, covered in brambles and flowers. In early morning, take the road east to the volcano. The scenery becomes increasing bare and finally you cross the barren Plaine des Sables, with the ruins of ancient craters. The road ends at the Pas de Bellecombe, on the northwestern rim of the caldera, where you look out from the edge of a 300 metre cliff at La Fournaise.
Here you leave the car, climb down the cliff-face, cross the lava fields and ascend to the rim of the Dolomieu Crater. This walk is 13 km and will take 4 – 5 hours there and back. It is best to start early, as in the afternoon clouds roll in and obscure the view. You will need good walking boots as you are walking over solidified lava, plus water, some warm clothing to take with you, sun cream, and a sunhat.