Switzerland Cave with an underground lake
Saint-Léonard underground lake
4 m deep, 0.3 km of galleries.
Boris Legradic Borsic ( talk ) (31 August 2009 (original upload date)) · CC BY-SA 3.0
The descent
4 metres down, to scale.
The real relief above Saint-Léonard underground lake, measured on the Copernicus model every 30 m, and the cave going down at the same vertical scale.
a person (2 m) would fit upside down 2.2 times.
The depth is the one published by those who explored it; the shape of the galleries is a sketch, not a survey.
4m
Depth
published (Wikidata)
0.3km
Galleries
surveyed length (Wikidata)
509m
Entrance altitude
published (Wikidata)
11°C
Inside, all year
the yearly average outside, at the entrance
637m
Rock above
the highest point within 1.5 km
Inside and outside
11 °C inside, all year.
Deep inside, a cave keeps the average temperature of the year outside: about 11 °C here, in January and in August. In July the afternoon reaches 25 °C at the entrance, 14 °C warmer than inside: take a jacket.
- 5°-3°Jan
- 6°-3°Feb
- 9°1°Mar
- 15°6°Apr
- 19°10°May
- 23°14°Jun
- 25°16°Jul
- 25°15°Aug
- 21°12°Sep
- 17°8°Oct
- 10°3°Nov
- 6°-1°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.
Lake in Saint-Léonard in the canton of Valais, Switzerland
Saint-Léonard underground lake is a cave with an underground lake in Switzerland. It goes down 4 m below the entrance and has 0.3 km of surveyed galleries. The entrance is at 509 m. It has an underground lake and stalactites and stalagmites. It is open to visitors.
Getting there.
- Show cave: open to visitorsticket requiredOfficial site↗
- Saint-Léonardnearest town · 0.8 km in a straight line
- Parking 100 m awaynearest car park in OpenStreetMap, straight line
- Viewpointsnearest viewpoint · 1.0 km from the entrance
- Bern Airport (BRN)nearest airport with scheduled flights · 73 km in a straight lineCar hire at BRN airport (Bern)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 kmLac Souterrain
- 4viewpoints within 3 kmVue sur le village de Lens and 3 more
- 7marked hiking routes within 3 km06-Tour pédestre du Val d'Hérens, Bisse d'Ayent, Bisse de Bitailla and 4 more
- 1climbing crags within 3 kmArbaz
- 29car parks within 2 km
- 1information boards and visitor centres within 3 km
- 30bus stops within 2 km
- 7campsites within 8 kmCamping Moubra, Stellplatz Lac Souterrain, Stellplatz Binii and 4 more
- 95hotels and guesthouses within 8 kmAux Bons Matins de Capella, 13 Etoiles, La Mijon and 92 more
- 32restaurants and cafés within 3 km
- springs within 2 km
- sinkholes within 3 km
- caving clubs and spots within 15 km
- named waterfalls within 4 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
- Saint-Léonard0.8 km in a straight line
- Grône2.6 km in a straight line
- Ayent3.1 km in a straight line
- Grimisuat3.2 km in a straight line
- Lens3.5 km in a straight line
- Chermignon-d'en Haut5.2 km in a straight line
- Vex5.3 km in a straight line
- Savièse6.2 km in a straight line
In our other atlases
What else is around Saint-Léonard underground lake.
The river at the entrance, the waterfalls, the lakes, the mountains and volcanoes above, the canyons, beaches and islands nearby — from our other atlases.
Peakyas25 mountains within 10 kmFigures 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 | 5 | 6 | 9 | 15 | 19 | 23 | 25 | 25 | 21 | 17 | 10 | 6 |
| Afternoon | 5 | 6 | 9 | 15 | 19 | 23 | 25 | 25 | 21 | 17 | 10 | 6 |
| Night | -3 | -3 | 1 | 6 | 10 | 14 | 16 | 15 | 12 | 8 | 3 | -1 |
| Rain (mm) | 85 | 67 | 84 | 83 | 130 | 122 | 125 | 132 | 84 | 87 | 87 | 92 |
| Rainy days | 12 | 12 | 14 | 15 | 18 | 18 | 17 | 16 | 14 | 13 | 14 | 14 |
| Sun hours/day | 3.3 | 4.4 | 5.5 | 6.3 | 6.6 | 8.5 | 8.9 | 7.9 | 6.9 | 5.0 | 3.1 | 2.6 |
| Snow on the ground (cm) | 35 | 40 | 29 | 13 | 7 | 2 | 1 | 1 | 3 | 8 | 15 | 24 |
| Afternoon | Afternoon | Night | Rain (mm) | Sun hours/day | |
|---|---|---|---|---|---|
| Jan | 5 | 5 | -3 | 85 | 3.3 |
| Feb | 6 | 6 | -3 | 67 | 4.4 |
| Mar | 9 | 9 | 1 | 84 | 5.5 |
| Apr | 15 | 15 | 6 | 83 | 6.3 |
| May | 19 | 19 | 10 | 130 | 6.6 |
| Jun | 23 | 23 | 14 | 122 | 8.5 |
| Jul | 25 | 25 | 16 | 125 | 8.9 |
| Aug | 25 | 25 | 15 | 132 | 7.9 |
| Sep | 21 | 21 | 12 | 84 | 6.9 |
| Oct | 17 | 17 | 8 | 87 | 5.0 |
| Nov | 10 | 10 | 3 | 87 | 3.1 |
| Dec | 6 | 6 | -1 | 92 | 2.6 |
Averages 1991–2020 (NASA POWER) for a cell about 55 km wide, brought to the altitude of the entrance (509 m) with the standard lapse rate. Not a forecast.
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 | 49% | 168% | 91% | 64% | 79% | 146% | 62% | 131% | 103% | 183% | 23% | 82% |
| 2021 | 138% | 60% | 62% | 56% | 105% | 116% | 176% | 59% | 92% | 56% | 65% | 131% |
| 2022 | 47% | 125% | 22% | 99% | 69% | 89% | 57% | 58% | 172% | 96% | 92% | 105% |
| 2023 | 65% | 22% | 147% | 129% | 103% | 72% | 88% | 109% | 85% | 139% | 245% | 182% |
| 2024 | 108% | 94% | 158% | 108% | 153% | 142% | 92% | 89% | 220% | 142% | 77% | 111% |
| 2025 | 124% | 44% | 59% | 108% | 92% | 85% | 124% | 108% | 188% | 114% | 107% | 23% |
130% or more: wet month 70% or less: dry month
Caves nearby.
Saint-Léonard underground lake
Switzerland
- 4 mDepth
- 0.3 kmGalleries
- 509 mEntrance altitude
- 11 °CInside, all year
Grotte aux Fées
Switzerland · 33 km
- —Depth
- —Galleries
- 531 mEntrance altitude
- 11 °CInside, all year
Gouffre Jean-Bernard
France · 51 km
- —Depth
- —Galleries
- 2,209 mEntrance altitude
- 0 °CInside, all year
Gouffre Mirolda
France · 54 km
- —Depth
- —Galleries
- 1,893 mEntrance altitude
- 2 °CInside, all year
Where these figures come from
| Name, type, published depth and length, visitors | Wikidata (Q387415) · 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.
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