Attraction · Saint-Léonard · Updated on 1 November 2026.
Underground lake is an attraction in Saint-Léonard, Valais/Wallis. This place has a story in the app. Within 200 m you'll find a public toilet, a bench and a water point.
Story · Underground lake
You're standing at the Saint-Léonard underground lake, in the Swiss canton of Valais. From up here there's not much to see, but beneath your feet lies something remarkable: the largest underground lake in Europe. It's about three hundred metres long and twenty metres wide.
Read the whole story in the Outdoor Pitstop app: check in at this place and it is yours (with Pro; new users are Pro for the first 4 weeks).
Source: OpenStreetMap and Wikidata.
8 photos from Wikimedia Commons. In the app you add your own photo when you are there.
The nearest pitstop of each kind within 1 km, as the crow flies. No bike pump or food stand within 1 km.
23 well-known points of interest nearby, those with an audio tour first.
Hear the story of Valère on the spot with the app
No, according to OpenStreetMap it is not wheelchair accessible.
Yes: a public toilet at 140 m and a water point at 200 m.
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