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Remember J. J. Tolkien's The Lord of The Rings when Bilbo meets Gollum and the ring? It happens in a spectacular cave filled with crystal-clear underground water. Perhaps we found this place in Switzerland while travelling through the Canton of Valais. 

It is known that the writer has travelled and stayed in Swiss Alps, so it might be true that his literary inspiration has also come from his travels. Discovering the St-Leonard Lake, which is the largest underground lake in Europe, might have also been on his agenda. 

The lake is just 5 min away from Sion, just a short ride from the highway with plenty of parking spaces. You have to walk up the hill for no more than 100 meters to get to the visitor centre. The entrance fee is really cheap, the only thing is that you might wait for the boat for 30 min or so. There is no possibility to enter the cave and have a sail on your own, therefore you must take a boat with a guide (who speaks several languages) to enjoy the natural beauty of the underground world. There's a small bar where you can sit and wait for your boat, if necessary. 

To enter the boat you have to go deep down the stairs where the boat will be waiting for you. Be aware that the temperature down below is always 15 degrees Celsius, so don't forget to bring your jacket with you to enjoy this pleasant coolness. Crystal waters are also rather cold - only 8-11 degrees but it won't stop you from immersing your palm to test the cold anyway. The trip will take around 30 min with the guide stopping on the way and telling the interesting facts and answering your questions. Be prepared for the big fish following you all the way around.

The cave and the lake are beautifully illuminated to enhance the visibility and provide with an artistic view. The end of the cave has its own holographic show when you can see butterflies flying or fish swimming on the wall. It dwells with a mystery but it also covers you in total calmness in a way of some type of relaxing therapy.

The lake is a place for romance, as it also offers private visits on a special boat with aperitif (reservation needed). Public events and concerts are held on regular basis.


Unfortunately, it's impossible to visit St-Leonard underground lake off-season. It closes for the visitors on September 22 and will be re-opened only on June 6, 2020. But it promises that next year a new visitor centre with a new shop, snacking area and conference room will be offered to the visitors (as the current facilities look really outdated).

It was fascinating to discover this peaceful place, which is open to the public since 1949, though it's existence was known long before to the people living around.

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