Opening dates : Summer 2026 - 01 june to 01 november

The Mer de Glace : a giant

Located on the northern slope of the Mont-Blanc massif, the Mer de Glace is the largest glacier in France. 
Almost 7 kilometres long and covering an area of about 40 km², it extends from an altitude of 3,900 metres to about 1,500 metres. Its thickness, once impressive, still reaches several hundred meters in places.

The Mer de Glace is a glacier in perpetual motion. Fed by the eternal snows of the surrounding peaks, it advances slowly, at an average speed of 70 meters per year at its center. However, like many Alpine glaciers, it is now suffering the effects of global warming, leading to a significant decline in its mass and extent.

Other activities

The Glaciorium

An interpretation centre to answer all the questions that visitors ask themselves when they are faced with a glacier such as the Mer de Glace. The Glaciorium also responds to...

The Cave

Dive into the heart of the glacier and discover an ephemeral work of art.An ephemeral work of art that the Claret family has been maintaining and renewing for 3 generations...

Hiking and walks

In winter, two magnificent snowshoe walks are mapped out. The routes are easy to meet, with a duration of about fifteen minutes, and ‘under the viaduct’, lasting about 45 minutes;...

Opening dates : Summer 2026 - 01 june to 01 november

Friday 17th July

Train services are running normally.

Gondola and ice cave are openned.

During the summer season until 30 August, the service will run daily from 8.00 am to 5.30 pm. 

  • 1st departure at 8.00am
  • Last ascent : 5.00 pm
  • Last descent : 5.30 pm

  • A train every hour or every 30 – or 20 – minutes depending on demand. 
  • NB: Last departure for visiting the ice cave at 3.30 pm