Aiguille du Midi's Famous Ice Tunnel Is Gone — For Now

The ice tunnel that has carried generations of mountaineers out of the Aiguille du Midi cable car station and onto the high ridge above Chamonix no longer exists. After days of failed attempts to stabilize the structure amid a punishing summer heatwave, crews from the Compagnie du Mont-Blanc dismantled the tunnel this week, closing off — for now — one of the most iconic access points in the Alps.

A landmark carved from decades of snow

Cut directly into the ice at 3,842 meters, the grotte de glace has for decades served as the gateway from the Aiguille du Midi's summit station to the exposed arête, the starting point for the Vallée Blanche and countless classic routes across the Mont-Blanc massif. Every climber heading for the Trois Monts route to Mont Blanc, or the long descent toward Italy, has passed beneath its icy roof.

According to the outdoor news site SnowBrains, the tunnel sits at the very top of the accumulation zone of the Glacier des Pèlerins, where enough snow and ice normally piles up each winter to keep the station's exit passable. This summer, that balance broke down.

Heat, then closure, then removal

The trouble began in late July, as France endured its fourth heatwave of the season. Local broadcaster ICI (formerly France Bleu) reported that the freezing level — the altitude above which temperatures stay below zero — hovered around 4,300 meters, well above the tunnel itself, while Haute-Savoie was placed under an orange heat alert. Mountaineers and guides began noticing meltwater trickling from the cave's exit.

The Compagnie du Mont-Blanc first closed the tunnel to climbers on Tuesday, August 4, describing the closure as a safety operation carried out in coordination with the town of Chamonix. The company said the classic route out onto the Aiguille du Midi arête would be off-limits to climbers for the day, and warned against lingering or gearing up beneath the weakened ice vault in the meantime. Le Dauphiné Libéré reported that guides were advising climbers to rope up instead in a more sheltered gallery nearby and cross the danger zone quickly.

The closure was extended into Wednesday, August 5, as the security operation continued, according to Radio Mont-Blanc. Speaking to ICI Pays de Savoie, Compagnie du Mont-Blanc chief executive Mathieu Dechavanne indicated the work would likely involve cutting away the cracked blocks of ice piece by piece.

By the end of the week, that process had gone further than a simple trim: the tunnel itself had to be removed entirely. SnowBrains, which had tracked the closure day by day, confirmed the dismantling and reported that the cable car's normal operations continued uninterrupted throughout, with sightseers still able to reach the summit's panoramic terraces even as mountaineers lost their usual exit route.

Not the first time — but a telling sign

Outdoor-industry outlet Outside.fr noted that this kind of intervention is exceptionally rare; the only real precedent was the historic heatwave of 2003, which similarly damaged the tunnel. The magazine's report placed the closure alongside another loss this summer — the disappearance of the "niche des Drus," a well-known rock formation on the Aiguille Verte massif, documented by mountain guide Fred Degoulet in July. It quoted veteran Chamonix guide Claude Jaccoux, 93, reflecting on how visibly the massif has changed over his lifetime, and framed both losses as signs that melting is no longer confined to distant glaciers but is now reaching the most familiar passages of high-altitude travel.

The ski-industry outlet The Ski Guru was careful to distinguish the tunnel closure from the unrelated, separately scheduled ice cave at Montenvers–Mer de Glace, a lower-altitude tourist attraction reached by cogwheel train that remained open on its normal summer schedule throughout.

What happens next

Despite the tunnel's removal, officials say the danger has passed rather than deepened: with the unstable ice gone, the immediate collapse risk to climbers and sightseers has been eliminated, and the cable car station's other functions are operating normally. SnowBrains reported that the tunnel is expected to rebuild itself naturally once winter snowfall resumes, as it has after previous damage — though for the rest of this summer, climbers bound for the Vallée Blanche and the high routes of the Mont-Blanc massif will have to find another way out.