Réserve naturelle nationale de la grotte du Carroussel

The Carroussel Cave Nature Reserve is a small but ecologically significant protected site in the Haute-Saône department of eastern France, spanning the communes of Port-sur-Saône and Conflandey. Covering just 2.3 hectares, it ranks among the most important bat hibernation sites in the Franche-Comté region.

Where exactly is the cave located?

The entrance opens in a cliff face on the right bank of the Saône river, in the heart of the river valley, facing due east at an altitude of roughly 220 meters. This orientation and rocky setting keep the interior of the cave cool and climatically stable for most of the year — precisely the conditions hibernating bats need to survive the winter without burning through their fat reserves too quickly.

Why was this site protected?

The reserve was created by decree on 27 March 1990 specifically to safeguard colonies of several bat species roosting in the underground cavity, including Schreiber's bent-winged bat. The Carroussel cave forms one link in a wider network of underground shelters used by these bats across Franche-Comté, which is why the site is included among areas designated under the EU Habitats Directive — both as part of the cavity network for Schreiber's bat and in connection with the broader Saône valley habitats.

Who manages the reserve today?

The official manager is CPEPESC Franche-Comté, an association dedicated to bat conservation and the protection of their habitats. It took on this role in November 1990, shortly after the reserve's creation, following a framework agreement signed with the local prefecture. The site is also listed in France's national ZNIEFF type 1 inventory, a classification reserved for areas recognized as ecologically valuable with well-documented flora and fauna.

Can visitors go inside the cave?

The Carroussel cave functions first and foremost as wildlife shelter rather than a conventional tourist attraction. Reserves of this kind in France are typically subject to access restrictions, especially during the bats' hibernation period, when even minor disturbances to temperature or noise levels can put the colony at risk. Visitors are generally limited to admiring the rock face and surrounding valley from the outside rather than entering the cavity itself.

What else is worth seeing nearby?

The Saône valley around the reserve offers scenic views of the river framed by limestone cliffs typical of this part of Haute-Saône. The nearby town of Port-sur-Saône makes a convenient base for exploring the wider area, while Conflandey, the second commune sharing the reserve's territory, adds another point of interest for those following the riverbank.

Frequently asked questions

How large is the Carroussel Cave Nature Reserve? The protected area covers 2.3 hectares.

When was the reserve established? It was created by a decree dated 27 March 1990.

Which species does the cave protect? Primarily bat colonies, including Schreiber's bent-winged bat, which use the cave as a hibernation site.

Is the cave open to visitors? As a nature reserve focused on protecting hibernating bats, access is restricted, so it is not a typical open-access tourist attraction.

Where precisely is it located? On the right bank of the Saône river, within the communes of Port-sur-Saône and Conflandey in the Haute-Saône department of France.