The Diagonale des Fous , also known as the Grand Raid de La Réunion , is one of the toughest ultra-trail races in the world. Every year, it attracts runners from all over the world, eager to take on an extreme course through the unique landscapes of the island of La Réunion. Nicknamed "the race of fools", this event tests the physical and mental endurance of each participant, on volcanic terrain, lush tropical forests, steep mountains and majestic cirques.
An extreme trail in the heart of the Indian Ocean
The Diagonale des Fous takes place every year in October on the island of La Réunion, a volcanic island located in the Indian Ocean. The course crosses the entire island from west to east, starting from Saint-Pierre to Saint-Denis , over a distance of 165 km with a positive elevation gain of 10,000 meters . What makes this race particularly challenging is not only the length and the elevation gain, but also the diversity of the terrain and the unpredictable weather conditions.
A journey through spectacular landscapes
The departure: Saint-Pierre and the climb towards the volcano
The race starts in Saint-Pierre , a town on the southwest coast of the island. From the start, the runners face steep climbs towards the Piton de la Fournaise Massif , one of the most active volcanoes in the world. This initial section is a real test of endurance, with rocky and volcanic trails that demand a lot of physical effort.
The cirques of Cilaos, Mafate and Salazie
One of the most feared and fascinating moments of the Diagonale des Fous is the passage through the cirques of Cilaos, Mafate and Salazie . These natural cirques, classified as UNESCO World Heritage Sites, offer breathtaking landscapes, but are also extremely difficult to cross. Each cirque has steep paths, steep climbs and technical descents, sometimes in very wet conditions. The riders must cross narrow and rocky passages, and manage the tropical humidity which can make the paths slippery.
The Mafate cirque , in particular, is known for its isolation. Accessible only on foot or by helicopter, this wild area reinforces the feeling of adventure for participants. This passage is a real physical challenge, but also a mental one, where each stride requires concentration and perseverance.
The ascent of Piton des Neiges
Piton des Neiges , which peaks at 3,070 meters above sea level, is one of the highest points of the race. The ascent of this iconic peak is one of the most difficult sections of the course. The climb is long, steep, and oxygen becomes scarcer as the runners gain altitude. Once at the top, the panoramic view of the island is breathtaking, but the runners cannot afford to relax, because the descent that follows is just as technical and demanding.
The plains and forest of Bébour
After crossing the cirques and climbing the Piton des Neiges, the runners still have to face the crossing of the Plaines des Cafres and des Sables , as well as the Bébour-Bélouve forest. This last section is particularly challenging due to the accumulated fatigue and the often muddy and slippery terrain. Roots, rocks and puddles make progress difficult, but this is where the participants' mental strength makes all the difference.
Arrival in Saint-Denis
After covering 165 km and climbing 10,000 meters of altitude difference, the runners finally reach the finish line in Saint-Denis , the capital of the island. This moment is full of emotion for all the finishers, who have overcome one of the greatest challenges of their lives. The inhabitants of Reunion, always enthusiastic, welcome the runners with warm encouragement, creating a unique and festive atmosphere.
Technical terrain and unpredictable weather
The Diagonale des Fous is not only known for its challenging course, but also for its often unpredictable weather conditions. Runners can face scorching heat in the lower parts of the island, especially in the cirques, and freezing temperatures at the top of the Piton des Neiges. Frequent tropical rains make the trails muddy and slippery, further increasing the difficulty of the race. It is not uncommon for thick fog or thunderstorms to make certain sections particularly dangerous.
A legendary race and trail heroes
The epic figures of the Diagonal
Many internationally renowned trail runners take part in the Diagonale des Fous, but only the most enduring manage to cross the finish line. Among the most famous runners are legends such as François d'Haene , Kilian Jornet and Antoine Guillon , who have all left their mark on this race with their exceptional performances. Women are not left out, with athletes such as Andrea Huser and Nathalie Mauclair , who have also shone on this legendary race.
A unique experience for amateurs and professionals
Although this race is a real challenge for the elite, it is also open to amateurs who wish to take on this extreme adventure. Finishing the Diagonale des Fous is an accomplishment in itself, regardless of the time taken. Runners often refer to this race as a "life experience", so intense is the physical and mental commitment.
Preparation for the Diagonale des Fous
Physical training
Participating in the Diagonale des Fous requires very rigorous physical preparation. Runners must train on varied terrain, including sessions in the mountains to accustom the body to the significant differences in altitude. Training on hills and descents is essential, as technical climbs and descents represent a large part of the course. Runners must also work on their endurance with long runs and races on terrain similar to that of the race.
Nutrition and hydration
Proper nutrition and hydration management is crucial to success in this race. Runners must carefully plan their nutrition before and during the race to avoid energy dips. Aid stations are distributed along the course, but self-sufficiency between aid stations is necessary. Hydration is equally important, especially in the hot and humid cirque sections.
The Diagonale des Fous, an extraordinary adventure
The Diagonale des Fous is much more than just an ultra-trail, it is a true human adventure. Crossing the island of La Réunion, facing technical and unpredictable terrain, and overcoming your own limits make this race one of the most legendary in the world. Whether you are a seasoned athlete or a trail enthusiast looking for an extreme challenge, the Diagonale des Fous is a unique experience that leaves an indelible mark on the mind of each participant.
If the Diagonale des Fous has fascinated you with its unique challenge and breathtaking landscapes, know that there are many other equally impressive trails across France. Discover our selection of the most challenging trails , to explore varied paths, from mountains to coasts, and immerse yourself in equally unforgettable adventures.
For hiking enthusiasts looking for challenges and breathtaking landscapes, explore our selection dedicated to the most beautiful trails in France . From the majestic Diagonale des Fous to other hidden gems, discover routes that promise unforgettable adventures and breathtaking panoramas. Visit our page to learn more and plan your next adventure on the French trails!
