Source Du Ruisseau De L'Ours Et Marais Des Hauts Buttés

The Source of the Ruisseau de l'Ours and the Marais des Hauts Buttés form a directed biological reserve (réserve biologique dirigée) located in the Croix-Scaille state forest, in the commune of Thilay in the Ardennes department, right next to the French-Belgian border. The protected area covers the spring where the Ruisseau de l'Ours stream originates and the adjoining Hauts Buttés peat bog, sitting on the Hauts Buttés plateau at roughly 500 metres above sea level, in a clearing surrounded by forest.

What is this reserve?

The reserve was established on 16 February 1982, with its boundaries and management status refined by a further decision on 25 April 1995. It covers 17.78 hectares and is protected as an area of particular ecological value under the management of the French National Forestry Office (ONF – Office National des Forêts). Its purpose is to preserve, in as natural a state as possible, the hydrological processes and vegetation typical of springs and upland peat bogs found in this part of the Ardennes.

Why is the Marais des Hauts Buttés significant?

The Hauts Buttés bog is also part of the Natura 2000 network, reflecting its recognised importance for biodiversity conservation at the European level. The plateau on which the bog lies forms a natural depression in the middle of a dense forest block, favouring water accumulation and the development of wetland vegetation that is uncommon in the lower-lying parts of the Ardennes. Because of its position right on the border with Belgium, the area forms part of the larger, cross-border Croix-Scaille natural complex, known for its well-preserved patches of forest and near-natural wetlands.

What can visitors see on site?

The reserve borders the source of the Ruisseau de l'Ours, a stream that rises here and continues its course through the surrounding forest. The site is both a starting point and a section of a hiking route roughly 11.1 kilometres long, which winds through the forests and wetlands of the Croix-Scaille plateau. The trail lets visitors see both the spring itself and the peat bogs around it, along with the forest landscape typical of this part of the Ardennes.

How to get there?

The area lies in the commune of Thilay, within the Croix-Scaille state forest, in the northern part of the Ardennes department, close to the Belgian border. Access is mainly on foot, via marked forest trails running through the Croix-Scaille complex.

Frequently asked questions

What is a réserve biologique dirigée? It is a French protection status for forest areas managed by the ONF, where the priority is to preserve specific habitats or species through targeted conservation actions, as opposed to integral reserves left entirely free of human intervention.

When was this reserve created? The reserve was established in 1982, with its rules refined in 1995.

How large is the protected area? The reserve covers 17.78 hectares of forest, spring, and peat bog.

Is the area part of the Natura 2000 network? Yes, the Marais des Hauts Buttés is included in the Natura 2000 network because of its ecological value.

Can the reserve be explored on foot? Yes, a hiking trail of about 11.1 km runs through the area, connecting the spring with the surrounding forests and wetlands of the Croix-Scaille plateau.