Cyprien Nicolas. Views from Morne Langevin. The Morne Langevin is a mountain peak on the island of Reunion, a French overseas department in the Indian Ocean sea. Located in the municipality of Saint-Joseph, which rises to 2380 meters along the cliff instead of plain Remparts River dominates Langevin sources, a river of Piton de la Fournaise s' flowing from the north to the wild south. It is reached by a trail that runs along the wall of the Sands of mountain pass called non Sables.