A little train heading into the mountain, a boat gliding across a lake hidden beneath the rock, a head torch sweeping over stalactites: going underground remains one of the outings that leave the strongest impression on children.
Worth knowing before you set off: underground, the temperature stays between 10 and 18 degrees all year round. It is the ideal outing when it is too hot outside, and a warm layer is essential even in the middle of August. Here are our five favourite underground adventures in French-speaking Switzerland.
Les Mines de Sel de Bex, by little train (VD)
Les Mines de Sel de Bex are the oldest salt mine still in operation in Switzerland. You board a little train that dives into the heart of the mountain, then explore immense galleries dug by hand, at a constant 18 degrees.
This is our number one recommendation for a first underground experience: the train helps younger children accept the darkness, and the visit is guided from start to finish.
The underground lake of Saint-Léonard, by boat (VS)
Between Sion and Sierre, the underground lake of Saint-Léonard is the largest natural underground lake in Europe. You glide across it in silence on a guided boat, the vault lit up just above your heads.
The experience is short, cool and genuinely magical. It does require sitting still and staying quiet for the crossing, though: keep it for children able to stay put.
Les Grottes de Vallorbe, an underground river and stalactites (VD)
In the heart of the Jura vaudois, les Grottes de Vallorbe give access to an underground river and a veritable forest of stalactites. You descend at your own pace, lamp and app in hand, through one of the finest cave networks in Switzerland.
The route is laid out but includes steps: be ready to carry the youngest.
The La Lée copper mine, “miner for a day” (VS)
In the val d’Anniviers, above Zinal, the La Lée copper mine is visited with a guide: 500 metres of galleries to explore. On Sundays, children become “miners for a day” and extract the copper ore themselves.
It is the one that leaves the most tangible memories: you go home with your own rock in your pocket. Allow for the approach walk in your planning, as the mine is reached on foot.
La Grotte aux Fées in Saint-Maurice, a lake and waterfall beneath the cliff (VS)
Between cliffs and abbey, la Grotte aux Fées has its own lake and an underground waterfall. The walk is short, mysterious and cool all year round: it is the coolest in our selection, at around 10 to 12 degrees.
What to know before you go down
- A warm layer, even in summer: underground, the temperature barely exceeds 18 degrees, and drops to around 10 degrees in some caves.
- Closed shoes with good grip: the ground is damp and often slippery.
- Anticipate the reaction to darkness: a child who is sensitive to the dark will be more comfortable in a lit mine visited by train than in a cave explored by lamp. Talk about it beforehand, not on site.
- Guided visits start at fixed times and fill up quickly in summer and during the holidays: check the times and book on the official websites.
- Strollers are impossible: steps, walkways and uneven ground. Bring a baby carrier.
Prefer to stay above ground? Discover our finest gorges, caves and waterfalls in the open air, several of which are free, and all our Nature & Animals activities.
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Frequently asked questions
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Michael @ Kidora
Kid Adventure Planner