Discovery trail: 1.5km
Marsh circuit: 2km
Created in 1993, the Chalmessin natural reserve is a natural treasure in the middle of the woods. Its 124 hectares, managed by the Conservatoire d'Espaces Naturels de Champagne-Ardenne (Champagne-Ardenne Conservatory of Natural Spaces), house ones of the most remarkable tuff marshes of the Langres plateau. Since the last Ice Age 8000 years ago, very specific conditions have allowed this valley to conserve typically mountainous flora and fauna. Discovery path freely accessible all year round or you can request a guided visit.
The Réserve Naturelle de Chalmessin (The Chalmessin Natural Reserve) and its 124 hectares house one of the most remarkable tuff marshes of the Langres plateau. Totally isolated on the forest massif, it is situated at the bottom of a valley called Combe Forquot, or the Vallée des Goulottes, which forms the upper Vallée de la Tille.
Since the last Ice Age 8000 years ago, very specific conditions have allowed this valley to conserve typically mountainous flora and fauna. Distinguished botanist from Haute-Marne, Pierre Fournier, wrote 70 years ago that it freezes in the valleys of the plateau at least once a month, even in July and August! The Langres plateau is the region of France in which this type of marsh is encountered most frequently. This little natural region unites characteristic elements at their root: a chalky subsoil, a cold climate and a dense river network.
Out of the hundred tuff marshes of the Langres plateau, Chalmessin is one of the best conserved. The majority of them suffered from the drainages and afforestation attempts of the 1950s.
The Réserve Naturelle de Chalmessin forms part of a network of around thirty protected spaces in the heart of the Langres plateau, in which there are 25 tuff marshes of the same type (but many marshes in the neighbouring Côte d'Or can be added to this number). It plays a fundamental role in the conservation of rare, relict or vassal genetic species heritage in this type of environment.