Mer de Glace at Chamonix: the Montenvers train since 1909 and the ice cave

The Montenvers train: 1909

The rack railway connecting Chamonix (1042m) to Montenvers (1913m) opened in part in 1908 and was inaugurated to Montenvers in 1909. It is one of France’s oldest tourist railways still in operation.

The 20-minute journey through the forest and slopes of the Mont-Blanc massif is itself a spectacle. The Montenvers arrival station sits at 1913m, overlooking the Mer de Glace.

Mer de Glace: documented retreat

The Mer de Glace is France’s largest glacier, approximately 7km in length, fed by the watersheds of Mont-Blanc and several neighbouring peaks. Its retreat is amongst the most closely monitored by glaciologists in the world.

Since the late nineteenth century, the glacier has retreated by more than 2km in length and has lost more than 150m of thickness at its front. This retreat has accelerated since the 1980s. Staircases are regularly added to provide access to the ice cave, which is carved annually into the glacier: the number of steps reflects the extent of the retreat.

The ice cave

Every year since the 1940s, an ice cave has been carved into the glacier. Access is via a cable car from Montenvers station, then down a long staircase, and one walks inside the glacier through illuminated galleries that reveal successive layers of ice.

An interpretation space for glaciers

At the Montenvers site, an interpretation space dedicated to glaciers, currently being renewed, explains their formation, dynamics and retreat.

Planning a stay in Chamonix

AEC Collection selects and represents premium chalets and apartments in the Chamonix valley. The Montenvers train departs from Chamonix station every 20-30 minutes in high season, with tickets available at the station or online.