Aven Armand

Louis Armand descended the shaft in 1897 with Edouard Martel's team and found a single chamber large enough to hold Notre-Dame de Paris, its floor covered in what has been called a forest of stone: around four hundred stalagmites built up by water falling from the roof about a hundred metres above, some slender and stacked like plates, the tallest over thirty metres and generally described as the tallest known stalagmite in the world. Visitors now descend by funicular through a tunnel rather than by rope. The cave lies under the Causse Mejean, a bare limestone plateau with almost no surface water.

What you actually see

• The stone forest - around four hundred stalagmites across one chamber floor.
• The great stalagmite - a column over thirty metres high.
• The single chamber - a hall large enough to contain a cathedral.
• The funicular descent - a tunnel railway down to the cave floor.

When to go

Year-round in season; the cave closes over winter, roughly November to March. It stays around ten degrees inside. Summer visits should be booked and are busiest midday.

Honest expectations

Only one chamber is shown, and the visit is about forty-five minutes on a guided route. It is cold and damp. The plateau approach roads are long and empty.

Nearby

The Gorges du Tarn lie north; Montpellier-le-Vieux is southwest.