Intro

Europe's largest subterranean lake that can be sailed upon lies between Sion and Sierre. The water grotto is easily accessible and there is a boat tour for viewing it. The guides on the boat tell visitors about the history of the cave and its geology.

Various types of stone glitter at a height of ten meters, their shapes reflected on the 6,000 square meter surface of the lake. Trout swim in the clear water and the only species that is actually native to this subterranean world, the fungus gnat, hangs its larvae upside down on the walls of the cave.

Viewing the subterranean lake of St-Léonard is a marvelous adventure. The 300 meter long and about 20 meter wide watery underworld is considered to be a place of special power. It has been accessible to tourists since 1949. Every year about 80,000 visitors are taken in large boats to see the lake. The famous speleologist Jean-Jacques Pittard is said to have been the first person to scientifically explore the cave.

The grotto can be hired for receptions or special occasions.

General information

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Season
All year
Time required
2 to 4 hours (half day)
Suitable for children with age
6 to 9 years, 10 to 13 years, 14+ years
Suitable for
Groups
Weather
Indoor and outdoor
Category
Education, Adventure, Nature

Group & pricing information

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Language
German, French, English
Group Size
20 - 120

Discover the surroundings

Overview

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Overview
St-Léonard
Valais
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Travel information: St-Léonard

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