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Photo: Camuspeleo, CC BY-SA 4.0 via Wikimedia Commons
One of the largest underground chambers in the world, so vast that it could hold Notre-Dame Cathedral. It is a geological marvel. Access is by guided tour only, with several options available, from accessible discovery tours to multi-hour caving expeditions. Booking in advance is essential.
La Verna is a show cave in the commune of Sainte-Engrâce in the department of Pyrénées-Atlantiques in France. 660 metres (2,170 ft) of mined tunnel leads into the Salle de la Verna, the largest chamber in a show cave in the world. It has a diameter of 250 metres (820 ft), a height of 194 metres (636 ft), a surface area of 5 hectares and a volume of 3.6 million cubic metres (130,000,000 cu ft). A river cascades into the chamber from halfway up the east wall, and sinks into boulders near the base of the chamber.
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