The Mer de Glace (“sea of ice”) is France’s longest glacier, about 7 km of ice flowing down the north side of the Mont Blanc massif above Chamonix. You reach it on the little red Montenvers rack train, 20 minutes from Chamonix up to a viewpoint at 1,913 metres, then ride a new gondola down towards the ice cave carved into the glacier each year. As of October 2026 a return ticket with the train, gondola, ice cave and Glaciorium costs €49.70 for an adult. The glacier is shrinking fast, and seeing it is now as much a lesson in climate change as a mountain view.
Right now in Mer de Glace
- Wed3–8°C37–47°F6 mm rain
- Thu1–5°C34–40°F18 mm rain
- Fri-6–4°C22–38°FMostly clear
Tickets and tours for Mer de Glace
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What it is and why it matters
The Mer de Glace forms where glaciers from the high peaks meet below the Aiguille du Midi and the Grandes Jorasses, then flows north towards the Chamonix valley. Travellers have come to look at it since the 18th century, and the Temple de la Nature at Montenvers, one of the first Alpine refuges, recalls those early visitors. Opposite the station rises the granite spire of the Drus.
Today the ice is far below the viewpoint. According to the Mont Blanc research centre CREA, the glacier’s snout has retreated more than 2.5 km since the 18th century, 400 metres of it in the last 20 years, and under pessimistic scenarios the Mer de Glace could disappear by 2100. Signs along the way down show where the surface stood in past decades. For the valley as a whole, see our Chamonix travel guide.
What you’ll see
The Montenvers train and viewpoint
The rack railway, opened in 1908, leaves from its station next to Chamonix’s SNCF station and climbs through forest to Montenvers at 1,913 metres. From the terrace you look up the glacier towards the Grandes Jorasses and across to the Drus. There is a restaurant, a bar and a small hotel, the Montenvers Refuge, if you want to stay the night.
The gondola and the ice cave
The old route to the ice meant hundreds of steps down the moraine, and the number grew every year as the glacier thinned. Since 2024 a 10-seat gondola carries visitors down from Montenvers; from its lower station, about 170 steps still lead to the ice cave at around 1,760 metres. The cave is dug fresh each season because the glacier moves, and inside it is close to freezing. The stairs make the cave unsuitable for wheelchairs, though the gondola itself is accessible.
The Glaciorium and Temple de la Nature
The Glaciorium, at the top station, is an exhibition on glaciers and climate, and the Temple de la Nature shows the history of the site with projections. Both are in the combined ticket.
Tickets, hours and seasons (as of October 2026)
- Ticket: adult return train + gondola + ice cave + Glaciorium €49.70. The MONT BLANC MultiPass, from €95.60 for adults, also covers Montenvers and the Aiguille du Midi.
- Autumn 2026: the train runs (on 4 October, 8:30–16:00). The gondola and ice cave closed on 28 September; the gondola, Glaciorium and Temple de la Nature reopen from 17 October to 1 November, but the ice cave stays closed. The train then closes from 2 November to 4 December for maintenance.
- Who can go: children from 12 months; dogs on a lead are allowed, with care on the cave stairs. Wheelchair users can ride the train with a companion, depending on the weather; tell staff when you buy tickets.
- Check first: the Compagnie du Mont-Blanc’s live page shows the day’s openings, weather and webcam.
Getting there
Montenvers station is a short walk from Chamonix centre and from the main SNCF station, served by the Mont Blanc Express from Saint-Gervais-Le Fayet and Martigny. Paid car parks are nearby, including the Planards. Hikers can walk the Grand Balcon Nord from the Plan de l’Aiguille mid-station of the Aiguille du Midi cable car to Montenvers and ride the train down.
When to go and how long to allow
Allow two to three hours for the train, gondola, cave and exhibitions, longer if you eat at the top or walk. Summer is the main season; go early to avoid the busiest trains, and pick a clear day for the views. It is much colder at the glacier than in town, so bring a warm layer even in July, and shoes with grip for the stairs.
Safety
- Never walk onto the glacier on your own. Crevasses hide under snow and debris; only go with a qualified guide and equipment.
- The moraine slopes are unstable, with falling stones. Stay on marked paths and stairs.
- In an emergency call 112.
Combine it with
On the same day, ride the Aiguille du Midi cable car for a close look at Mont Blanc, or walk the Grand Balcon Nord. Our hiking guide has more trails in the valley. From Lyon or Paris, Chamonix makes a good Alpine leg of a France trip.
Mer de Glace FAQ
How much does it cost to visit the Mer de Glace?
As of October 2026, €49.70 for an adult return ticket covering the Montenvers train, the gondola, the ice cave and the Glaciorium. The MONT BLANC MultiPass also includes it.
Is the Mer de Glace ice cave open?
Not in autumn 2026: it closed on 28 September and stays closed during the 17 October to 1 November reopening of the gondola and Glaciorium. Check the operator’s annual openings before you go.
How many steps are there to the Mer de Glace ice cave?
About 170 steps from the lower station of the gondola, which opened in 2024 and replaced most of the old, much longer staircase. The cave is not accessible to wheelchairs.
How long does the Montenvers train take?
About 20 minutes from Chamonix (1,035 m) to Montenvers (1,913 m).
Is the Mer de Glace disappearing?
It is shrinking fast. Its snout has retreated more than 2.5 km since the 18th century, 400 metres in the last 20 years, and researchers say it could vanish by 2100 under pessimistic scenarios.
Can I walk on the Mer de Glace?
Only with a qualified mountain guide and the right equipment. On your own, stay on the paths, stairs and the ice cave.
Sources
Researched and last reviewed by TravelerCenter on 4 October 2026. Train, gondola, ice cave, prices and 2026 dates: the Compagnie du Mont-Blanc; glacier retreat: CREA Mont-Blanc; the gondola’s opening year: regional press. Opening dates change with maintenance and conditions, so check the live page before you go.
Data: Weather: MET Norway (CC BY 4.0) · Rates: ECB · Costs: World Bank ICP and price levels · Wikidata (CC0)