Neptune Caves

The Neptune Caves (French: Grottes de Neptune), also known as the Grottes de l'Adugeoir are a series of natural caves located in Wallonia near Petigny in the municipality of Couvin, Belgium. They are located on the Eau Noire river, a tributary of the Meuse. Many of the chambers are accessible to the public via a guided tour, partially via boat on the underground river.