Grottes de Neptune

Grottes de l'Adugeoir - Grottes de Petigny

Useful Information

Location: Petigny
Open: FEB to MAR Sat, Sun 10:30-12, 13:30-16.
APR to JUN Mon-Tue, Thu-Sun 10-12, 13:30-18.
JUL to AUG daily 10-12, 13:30-18.
SEP Mon-Tue, Thu-Sun 10-12, 13:30-18.
OCT to DEC Sat, Sun 10:30-12, 13:30-16.
JAN closed.
Fee: Adults EUR 8, Children (4-12) EUR 5. Groups (20+): Adults EUR 7, Children (4-12) EUR 4.50.
Combined ticket with Abime: Adults EUR 12, Children (4-12) EUR 7. Groups (20+): Adults EUR 10, Children (4-12) EUR 6.
Classification: SpeleologyKarst cave Speleologyriver cave.
Light: electric.
Dimension: T=12°C.
Guided tours: D=45min.
Address: Grottes Neptune, Tel: +32-60311954, Fax: +32-60399771. E-mail: contact
Holding des Fagnes sprl, Route de l'Adugeoir, 5660 Petigny, Tel: +32-71558811, Fax: +32-71596322.
Didier Dufrane, Cell: +32-475-484331. E-mail: contact
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.


1888 discovered by by ExplainE.A. Martel.
1932 electric light.
1952 opened as a show cave.
1972 sound and light show and boat trip added to the tour.
1980 renamed Grottes de Neptune.


Grottes de Neptune is entered at a fossil level with beautiful concretions. The tour goes down through another level to a river cave. Here a boat is entered and this lowest level is visited on a twenty minutes boat trip. The cave river is called Eau Noire (black water).

A guided tour takes the visitor on a journey of discovery in a natural setting of stunning beauty, along the foot of shimmering limestone cliff.

A walkway overlooking the wild and meandering river "Eau Noire" [The Black Water], crosses in front of an impressive porch which swallows up the river. The visit continues into the two upper galleries of the Caves of Neptune, with their superb rock formations sculptured by nature. The visit culminates in a 20 minute boat ride along an underground river, 10m below the level of the "Eau Noire". The journey is enhanced with an unusual "music & light" display, which, it is claimed is unique in Europe. During this display there are a number of lively waterfalls which form an impressive backdrop to the scene. The music of Vangélis and the stroboscopic light effects makes this a truly magical event which will live in the mind of the visitor forever.

Text by Tony Oldham (2002). With kind permission.