Grotte du Foulon

Site Géologique du Foulon

Useful Information

Location: Châteaudun
Open: OCT to MAR Sat, Sun Hol 14-18.
APR to MAY daily 14-18.
JUN to SEP Tue-Sun 10-12, 14-18.
Last admission 45 min befor closing.
Fee: Adults EUR 10, Children (5-18) EUR 5, Children (0-4) free.
Groups (+): Adults EUR , Children (3-18) EUR .
Classification: Speleologyerosional cave SubterraneaRock Mine
Light: LightIncandescent Electric Light System
Guided tours: L=800 m.
Address: Grotte du Foulon, 35 rue des Fouleries, 28200 Chateaudun, Tel: +33-237-451960, Fax: +33-237-458002. 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.


1723 used as a refuge during the great fire.


The Grotte du Foulon is basically a natural cave formed by erosion. The cave was later enlarged by quarrying, when the rocks to build the foundations of the castle were quarried. The resulting cavern was used as a shelter during the great fire in 1723.

The cave is an extraordinary geotope. Being not a karst cave there are actually very few speleothems like stalactites and stalagmites. On the other hand the chalk, a soft form of limestone, contains the highest concentration of chalcedony and quartz geodes known in Europe. This is what is actually called flintstone. The cave has already been a quarry during the Palaeolithic, when people were digging for the valuable flintstones.

This is a cave with a view, the entrance room with 255 m² offers a great view on the castle and the Loire valley. The room with belvédère is rent for seminars, weddings and other events. It is also used as picnic area for school classes.