Last month, a large rockfall swept down the south face of the Aiguille du Midi in the Mont Blanc massif of the French Alps. It has now been estimated that approximately 523 cubic meters broke away, the equivalent of 15 shipping containers of rock.
The scar from the missing rock is clearly visible, and a pile of fresh debris now sits at the base. In the days before and since the fall, climbers have reported cracking sounds and traces of runoff on the south face, suggesting that the recent slide won’t be the last.
On July 3, one user on the UK Climbing forum wrote, “Several teams have reported signs of an impending collapse: unusual noises (creaking, cracking, etc.), vibrations coming from the wall, and the sound of water flowing without any visible water in the Kohlmann/Clair de Lune area (extreme right hand side) of the south face of the Aiguille du Midi. A 12-meter block fell down a few weeks ago. Probably best to avoid in this hot weather!”
The 1st june rockfall at Aiguille du Midi south face was 523 m3! 🔥
Cracking noises and runoff traces above the scar (small red circle) indicate thawing permafrost and that the upper slab could fall as well! 🌊
Be careful when passing through this area! ⚠️
Data/analysis: Xavier Cailhol 🙏
— Melaine Le Roy (@subfossilguy.bsky.social) 9 July 2025 at 13:24
Classic climbing area under threat
The Aiguille du Midi (3,842m) is a popular climbing area. Its south face features classic granite routes such as the Rebuffat–Baquet and the Contamine. These climbs are close to the top of the Aiguille cable car and popular early in the summer.
But in recent years, the face has become much less predictable. Warmer summers have melted the permafrost that once glued the mountain together, leading to a steady but unpredictable increase in rockfall.
Since the early 2010s, climbers and guides have reported more severe rockfalls across the Alps. To name just a few: In 2018, a huge chunk of rock from the south face of the Trident du Tacul near the Grand Capucin came crashing down. In 2023, large rockfalls took place on the Aiguille du Midi and Mount Pelvoux. Then in 2024, part of the west face of the Dru, below the Bonatti Pillar, fell.
Rock avalanche deposit from 1st June below Aiguille du Midi south face! 🔥
📷 Xavier Cailhol (05 July) and Philippe Batoux (1st June)
Look how much snow disappeared in June! 😱 pic.twitter.com/z6yfp2G4rE— Melaine Le Roy (@subfossilguy) July 5, 2025
Some of these events have destroyed climbing routes entirely or forced the establishment of new lines. The Aiguille du Midi itself has seen smaller rockfalls almost every year, but the June 2025 collapse is one of the largest.
As the Alps continue to warm, events like this are becoming part of the landscape. For climbers and visitors, it’s a reminder of how fragile the high alpine environment is.
