The Mer de Glace in Chamonix: ice cave, stairs, 2026 prices and a retreating glacier

The Mer de Glace is the largest glacier in France, and one of the first places of Alpine tourism. People have ridden up from Chamonix on the Montenvers train for more than a century, to see the ice from above and then go down into a cave dug inside it.

What you see today is no longer the postcard: the glacier has sunk and pulled back, and reaching the ice now means a long staircase. That is precisely what makes the visit interesting, as long as you know what you have come for. The train itself, its timetable and its tickets are in our Montenvers train guide.

Our tip: Go down to the ice cave first, then visit the viewpoint and the exhibition: the steps are easier to climb back in the cool, before the next trains arrive.

What can you see from Montenvers?

From the Montenvers terrace, at 1,913 m, the view takes in the glacial valley, the Grandes Jorasses at the end and the Mont Blanc massif. It is one of the great panoramas of the valley, reachable with no technical skills.

But you are looking at the glacier from above, over a tongue of ice that has dropped a great deal. In summer the view is often dominated by rock, grey moraines and steps, far more than by the blue ice of the posters. The old photos displayed on site show a glacier almost level with the station: the comparison is striking.

The site includes the rack railway station, the Grand Hôtel du Montenvers, restaurants, the Glaciorium, a gondola down towards the ice and the ice cave when it is open.

How do you get down to the ice cave?

By gondola, then on foot. The gondola does not drop you at the cave entrance: you have to carry on down a route of stairs, several hundred steps to go down and then climb back up. The figure in old guidebooks is no longer right: the staircase gets longer every year as the ice drops, so keep some energy for the climb back up.

Count the climb back up in your effort, especially with young children, in bad weather or with weak knees. Someone who has difficulty walking can reach Montenvers by train without being able to go down to the ice.

What exactly is the ice cave?

An artificial tunnel, dug and maintained in the ice. Because the glacier moves and changes shape, it has to be dug out again regularly, sometimes in a new spot. It is neither a natural cavity nor a fixed place: the blue walls, sculptures and lighting in the photos belong to a tourist installation.

The route is short, cold, sometimes wet and slippery. It can disappoint anyone picturing a vast cavern; it remains a rare experience, being inside a living glacier. No official visit time is published, and the cave has no separate price: it is included in the full package.

When are the ice cave and the gondola open?

Each facility has its own calendar, and that is the source of most disappointments: the train can be running while the cave is closed.

For the cave's reopening, two official sources disagree: the tourist office announces 19 December 2026, the operator's live opening page 17 December 2026. Do not book the full package for those days without checking.

These timetables do not guarantee that every facility is open: weather, works and safety on the glacier can close the gondola or the cave at short notice. On the day, check the opening page and the ticket office.

How much does a visit to the Mer de Glace cost?

The "Voyage Mer de Glace" package includes the train, the gondola, the exhibitions, the Glaciorium and the ice cave when it is open. 2026 prices:

A local tourism website shows €154 for the family package, the tourist office €148.30: check when you pay. The package price is still due if the cave is closed: check whether it is open that morning. For under-5s, ask about the fare at the ticket desk.

If only the viewpoint interests you, the train-only ticket is enough. The full package is only worth the money if the cave is open and you are ready for the stairs.

What do the figures on the glacier's retreat show?

Scientific measurements distinguish two things that should not be confused: the retreat of the front, which is horizontal, and the thinning of the tongue, which is vertical.

• Retreat of the front: 35 metres a year on average between 1995 and 2015, according to a modelling study published in 2020.
• Projections: 60 to 85 metres a year between 2020 and 2030, 65 to 95 metres a year between 2030 and 2040, more than 90 metres a year after that. These are scenarios, not measurements.
• Thinning: about 1 metre a year between 1979 and 1994, then more than 4 metres a year between 2000 and 2008 on the tongue of the Mer de Glace, according to a study in the Journal of Glaciology published in 2026.

No simple public series gives the thickness lost year by year. But these two figures are enough to explain the staircase: ice that drops several metres a year moves the cave that much further from the gondola. The Glaciorium tells this story, and that is where the visit takes on its meaning.

Is the Glaciorium worth the detour?

Yes, especially in bad weather or with a family. It is an interpretation centre devoted to glaciology and the history of the Mer de Glace: neither a cave nor access to the glacier, but the place where you understand what you have just seen.

The Grand Hôtel du Montenvers, next door, recalls the time when the site was a holiday destination in its own right, before quick excursions. It is part of the scenery, not part of the package.

Can you go on foot or in winter?

On foot, yes: the Mer de Glace path climbs to Montenvers from Chamonix, with about 1,000 metres of ascent. It is a real hike, and it does not spare you the stairs to the cave: arriving on foot, you still have to go down and come back up. The routes are in our guide to hiking in Chamonix.

In winter, the site reopens on 5 December 2026. It appeals to the non-skiers of a ski resort, with the ice cave from mid-December, but visibility and pedestrian access are trickier. The Mer de Glace is also the finish of the Vallée Blanche, which skiers leave by gondola and train.

Montenvers station is behind the SNCF station: come on foot or by bus (see getting around Chamonix), or park at the Planards car park right next door, detailed in parking in Chamonix. For families, the Glaciorium and the train are the real highlights, see also when to go to Chamonix.

Possible disappointments, and how to avoid them

• The cave closed while the train is running. Check on the day, especially in September, October and early winter.
• The stairs. Plan for the climb back, and give up without regret with a tired child.
• The distant glacier. Do not come for the blue ice of the posters, come to understand a glacier that is disappearing.
• The crowds. In high season the train, gondola, stairs and restaurants are packed: take the first departure.
• Overcast weather. The panorama is half the visit: without it, the price weighs heavily.

To compare with the other high-altitude sites, see the Aiguille du Midi, Le Brévent and things to do in Chamonix. The valley's other landmarks are in the Landmarks section.

Sources

Sources: Montenvers-Mer de Glace and Compagnie du Mont-Blanc (2026 gondola and ice cave calendar, packages, live opening page), Chamonix Tourist Office (Mer de Glace and Montenvers train, winter 2026-2027 calendar, 2026 prices), modelling study of the front's retreat published in 2020, thinning study published in the Journal of Glaciology in 2026.

The number of steps in 2026, the time needed for the ice cave, the list of free entries and accessibility facility by facility are not published. Two reopening dates for the cave exist side by side, and we quote both. Research carried out on 27 October 2026.