The Plaine des Sables is the result of several collapses which occurred 65 and 61 million years ago, and of phases of fillings by the lava of the Piton de la Fournaise. The most recent eruption, which occurred approximately 1.000 years ago, is from Piton Chisny (at the end of the strait road, on the right) from which the lapillis covered all the plain.