Neptune Caves
The Neptune Caves (French: Grottes de Neptune), also known as the Grottes de l'Adugeoir are a series of natural caves 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.
Coordinates: 50°3′57.73″N 4°30′43.32″E / 50.0660361°N 4.5120333°E
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