Rivière Souterraine de Labouiche

The Pyrenees

Deep beneath the village of Labouiche, 6km northwest of Foix, flows Europe’s longest navigable underground river. Discovered in 1908 by a local doctor, it’s been open to the public since 1938. Barge trips lasting 75 minutes run for about 1.5km along its underground course, with guides pulling the boats along by ropes attached to the ceiling, and walkways entering more caverns and eerie chambers.

The highlight of the visit is saved for the end: a clattering waterfall known as the Cascade Salette, which tumbles into a sparkling turquoise pool. Depending on rainfall, the waterfall’s speed can vary anywhere from 100L to 1500L litres per second. It’s all quite touristy, but the kids are bound to love it.

Best of all on a blazing summer’s day, the caves hover at a cool constant temperature of 13˚C.