Anse Castalia

Grotte de l'Anse Castalia is a limestone cave carved into the cliffs near Anse-Bertrand, containing a small interior beach. Turquoise waves from the Atlantic Ocean surge regularly through the cave opening, creating a dynamic water-filled space inside.

This cave remained unknown to outsiders until 2018, when social media brought it to global attention. The sudden exposure transformed it from a local secret into a destination drawing visitors from around the world.

This formation shows how the ocean carves through limestone over centuries. Visitors can see directly how wave action has shaped the northern coastline of Grande-Terre.

Reaching this location takes about 20 minutes on foot via a marked trail starting from road D122, followed by a steep descent where a rope aids the passage. Wear sturdy shoes with good grip and plan your visit around calmer sea conditions for safer exploration inside.

The water inside displays a distinctive turquoise color caused by the interaction between limestone sand and filtered light, setting it apart from other sea caves in the archipelago. This interplay creates an uncommonly vivid hue that changes throughout the day as sunlight enters through the opening.