France Ice cave
Mer de Glace ice cave
0 °C inside, all year.
Tiia Monto · CC BY-SA 3.0
The descent
The entrance, at 1,760 m.
The real relief above Mer de Glace ice cave, measured on the Copernicus model every 30 m, and the cave going down at the same vertical scale.
The depth is the one published by those who explored it; the shape of the galleries is a sketch, not a survey. No depth has been published for this cave yet.
1,760m
Entrance altitude
published (Wikidata)
0°C
Inside, all year
the yearly average outside, at the entrance
925m
Rock above
the highest point within 1.5 km
Inside and outside
0 °C inside, all year.
Cold winter air sinks into the cave and stays trapped: the ice lasts all year, even when it is hot outside. In July the afternoon reaches 18 °C at the entrance, 18 °C warmer than inside: take a jacket.
- -3°-11°Jan
- -2°-11°Feb
- 1°-7°Mar
- 7°-2°Apr
- 12°2°May
- 16°6°Jun
- 18°8°Jul
- 18°7°Aug
- 14°4°Sep
- 10°0°Oct
- 3°-5°Nov
- -1°-9°Dec
Outside: afternoon and night averages for 1991–2020 (NASA POWER) brought to the altitude of the entrance. Inside: the yearly average, which deep parts of a cave keep. Near the entrance it follows the weather a little.
Ice cave in France
Mer de Glace ice cave is a ice cave in France. The entrance is at 1,760 m. It has ice all year. It is open to visitors.
Getting there.
- Show cave: open to visitorsUsually with a guided tour; check times and tickets on the official site.
- Chamonix-Mont-Blancnearest town · 4.1 km in a straight line
- Parking 2,400 m awaynearest car park in OpenStreetMap, straight line
- Viewpointsnearest viewpoint · 0.6 km from the entrance
- Annecy Meythet airport (NCY)nearest airport with scheduled flights · 64 km in a straight lineCar hire at GVA airport (Geneva)Discover Cars · sponsored link↗
Plan the visit
Guided tours, a bed nearby, a car.
Some links above are affiliate links: if you book through them we may earn a commission, at no extra cost to you. It never changes what the data on this page says.
From above.
The ground above the cave, with the relief shaded, the line of the section and what people have mapped around the entrance.
N
1.5 km
Sentinel-2 cloudless 2016 (EOX, CC BY 4.0), 6.0 × 6.0 km, north up. The line is the section above. Points © OpenStreetMap contributors.
Around the entrance.
- 1other cave entrances within 3 kmGrotte de glace
- 10viewpoints within 3 kmSignal Forbes, Les Sources de l'Arveyron, Point de vue sur la Mer de Glace and 7 more
- 56marked hiking routes within 3 kmSentier des Gardes, Plan de l'Aiguille - Montenvers, Rocher des Mottets - Montenvers and 53 more
- 11climbing crags within 3 kmDalle du Montenvers, Aiguille des Grands Chamoz, Aiguille du Grepon and 8 more
- 1named waterfalls within 4 kmCascade de Blaitière
- 3car parks within 2 km
- 5information boards and visitor centres within 3 km
- 21campsites within 8 kmBivouac du Rognon des Drus, Camping Les Arolles, Boerne and 18 more
- 93hotels and guesthouses within 8 kmHôtel Eden, Refuge de la Charpoua, Le Morgane and 90 more
- 10restaurants and cafés within 3 km
- springs within 2 km
- sinkholes within 3 km
- caving clubs and spots within 15 km
- bus stops within 2 km
Counted in OpenStreetMap, the map anyone can edit, around the entrance. A low number may just mean nobody has mapped it yet. © OpenStreetMap contributors (ODbL).
Towns nearby
- Chamonix-Mont-Blanc4.1 km in a straight line
- Les Houches9.7 km in a straight line
- Courmayeur15 km in a straight line
- Saint-Gervais-les-Bains16 km in a straight line
- Passy18 km in a straight line
- Les Contamines-Montjoie19 km in a straight line
- Martigny-Combe20 km in a straight line
- Orsières21 km in a straight line
In our other atlases
What else is around Mer de Glace ice cave.
The river at the entrance, the waterfalls, the lakes, the mountains and volcanoes above, the canyons, beaches and islands nearby — from our other atlases.
Figures from the sister sites' databases (Wikidata, HydroATLAS, GeoNames, NOAA, OpenStreetMap). Links open when each site is online.
Month by month
The weather outside, at the entrance.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Afternoon | -3 | -2 | 1 | 7 | 12 | 16 | 18 | 18 | 14 | 10 | 3 | -1 |
| Afternoon | -3 | -2 | 1 | 7 | 12 | 16 | 18 | 18 | 14 | 10 | 3 | -1 |
| Night | -11 | -11 | -7 | -2 | 2 | 6 | 8 | 7 | 4 | 0 | -5 | -9 |
| Rain (mm) | 107 | 77 | 94 | 74 | 117 | 105 | 103 | 105 | 76 | 86 | 94 | 110 |
| Rainy days | 12 | 11 | 13 | 13 | 18 | 16 | 15 | 14 | 13 | 13 | 14 | 14 |
| Sun hours/day | 3.3 | 4.5 | 5.5 | 6.3 | 6.6 | 8.5 | 8.8 | 7.9 | 6.9 | 5.0 | 3.1 | 2.6 |
| Snow on the ground (cm) | 49 | 62 | 46 | 15 | 6 | 1 | 0 | 1 | 3 | 7 | 15 | 29 |
| Afternoon | Afternoon | Night | Rain (mm) | Sun hours/day | |
|---|---|---|---|---|---|
| Jan | -3 | -3 | -11 | 107 | 3.3 |
| Feb | -2 | -2 | -11 | 77 | 4.5 |
| Mar | 1 | 1 | -7 | 94 | 5.5 |
| Apr | 7 | 7 | -2 | 74 | 6.3 |
| May | 12 | 12 | 2 | 117 | 6.6 |
| Jun | 16 | 16 | 6 | 105 | 8.5 |
| Jul | 18 | 18 | 8 | 103 | 8.8 |
| Aug | 18 | 18 | 7 | 105 | 7.9 |
| Sep | 14 | 14 | 4 | 76 | 6.9 |
| Oct | 10 | 10 | 0 | 86 | 5.0 |
| Nov | 3 | 3 | -5 | 94 | 3.1 |
| Dec | -1 | -1 | -9 | 110 | 2.6 |
Averages 1991–2020 (NASA POWER) for a cell about 55 km wide, brought to the altitude of the entrance (1,760 m) with the standard lapse rate. Not a forecast.
Photographs
Inside and around.
Recent years
Wet years, dry years.
Rain of each month as a share of the 1991–2020 average. A dry year means a lower river and hotter rock; a wet one, more water in the gorge.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2020 | 54% | 206% | 105% | 67% | 97% | 145% | 50% | 116% | 136% | 209% | 24% | 70% |
| 2021 | 146% | 67% | 73% | 63% | 124% | 103% | 147% | 64% | 93% | 62% | 59% | 162% |
| 2022 | 39% | 119% | 19% | 126% | 57% | 75% | 33% | 55% | 179% | 107% | 104% | 113% |
| 2023 | 72% | 8% | 186% | 138% | 76% | 101% | 68% | 101% | 87% | 167% | 272% | 194% |
| 2024 | 101% | 88% | 142% | 128% | 156% | 161% | 102% | 78% | 280% | 175% | 79% | 110% |
| 2025 | 124% | 39% | 41% | 141% | 88% | 92% | 102% | 91% | 175% | 157% | 106% | 28% |
130% or more: wet month 70% or less: dry month
Caves nearby.
Mer de Glace ice cave
France
- —Depth
- —Galleries
- 1,760 mEntrance altitude
- 0 °CInside, all year
Gouffre Jean-Bernard
France · 22 km
- —Depth
- —Galleries
- 2,209 mEntrance altitude
- 0 °CInside, all year
Gouffre Mirolda
France · 21 km
- —Depth
- —Galleries
- 1,893 mEntrance altitude
- 2 °CInside, all year
Saint-Léonard underground lake
Switzerland · 53 km
- 4 mDepth
- 0.3 kmGalleries
- 509 mEntrance altitude
- 11 °CInside, all year
Where these figures come from
| Name, type, published depth and length, visitors | Wikidata (Q30737737) · CC0 |
|---|---|
| The relief above, the entrance altitude, the section and the 3D model | Copernicus DEM GLO-30 · © DLR e.V., © Airbus Defence and Space GmbH, Copernicus/ESA |
| Climate | NASA POWER, 1991–2020 |
| Entrances, springs, sinkholes, opening hours and what is around | © OpenStreetMap contributors · ODbL |
| Images | EOX Sentinel-2 cloudless 2016 · CC BY 4.0; Wikimedia Commons |
| Rivers, waterfalls, lakes, mountains, canyons, beaches and islands nearby | Coastya, Lakeyas, Peakyas, Cascadyas, Islandyas, Riveryas |
Every figure is an average, an estimate or a count from a public dataset. Licences and methods: data sources.
The family
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