Trou de Fer, Canyon in Salazie, La Réunion, France

Trou de Fer is a deep canyon in Réunion carved through volcanic rock, featuring multiple waterfalls that plunge into a narrow gorge with vertical stone walls. Water rushes down the cliffs and pools at the bottom, surrounded by lush vegetation clinging to the rocky slopes.

The first attempt to descend the gorge, led by Pascal Colas in 1989, failed in torrential rain. A second expedition succeeded in October 1990 with Colas, Marie-Anne Chamel, Patrick Moret and Vincent Terrisse, filmed by Ushuaïa and TF1; it lasted over two weeks and used 15 porters. A sealed canister lost the previous year was found intact with its film in a cave in the Bras de Caverne.

The name "Trou de Fer", Iron Hole, comes from the dark rock of its walls. Since the 1990 expedition filmed by Ushuaïa, the canyon has been a regular stop for helicopter tours from the west coast or from Saint-Pierre-Pierrefonds airport. A belvedere reached on foot gives a view, though mist often hides the depression.

A viewpoint over the canyon is reached by car then a few hours' walk along an easy forest path, but mist often hides the depression even early in the morning. The canyon floor itself is reached only by rope, and the first descent, led by Pascal Colas in October 1990, needed 15 porters and over two weeks. Helicopter overflights leave from the west coast or Saint-Pierre-Pierrefonds airport.

The slot canyon at the base, about 3 km long, is often dammed by debris jams that form lakes, among them the "Lake of the Eel". Where the Bras de Caverne falls meet this corridor, a 90-degree drop known as the "Washing Machine" soaks anyone standing near its base with mist.