Aiguille de Prony

This gigantic chimney is not a coral formation but was created when a surge of fresh water formed at a depth of 38 metres and rose to 2 metres below the surface. Think of it as a mineral cathedral produced from the depths of the sea.

Today it is a popular diving spot: the fish quite enjoy the heat released from the cavity. The needle continues to grow as it produces its limestone matrix. As well as housing a thriving community of bivalves, the site is a spawning ground for loaches in...