Pont Granval

Pont Granval is a directed biological reserve (réserve biologique dirigée) located in the heart of the Forêt Domaniale de Marly, in the Yvelines department of the Île-de-France region, near the communes of Saint-Benoît and Auffargis. The reserve was established on 7 December 1988 and is managed by the French National Forestry Office (Office National des Forêts, ONF). It covers an area of 32.86 hectares and is classified under IUCN Category IV, a designation for protected areas managed mainly for the conservation of specific habitats or species.

Where exactly is Pont Granval?

The reserve sits within a well-known section of the Forêt de Marly called the Bois des Cinq-Cents Arpents (literally, the "Wood of Five Hundred Arpents," an old French unit of land area). Its coordinates are approximately 48.6904 N, 1.91372 E. The Forêt de Marly itself spans more than 2,000 hectares between Saint-Germain-en-Laye and Versailles, roughly 15 km west of Paris, making the reserve an easy destination for residents of the capital looking for accessible woodland without leaving the region.

What is being protected here?

The "directed biological reserve" status is granted to sections of ONF-managed forest in order to protect habitats considered remarkable or representative of a given forest environment. At Pont Granval, this means the area is subject to conservation-oriented management, meaning limited human intervention intended to let the forest develop in a way close to its natural state. The reserve's tree cover is dominated by large oaks and chestnuts, and the age of many trees gives parts of the forest the character of old-growth woodland. This environment supports forest wildlife typical of the region, including roe deer, red deer and wild boar, which can be found within the reserve and its surroundings.

Can you visit Pont Granval?

Yes. A walking trail known as "Réserve du Pont Granval – Bois des Cinq-Cents Arpents" runs through the reserve and the adjoining section of the Forêt de Marly, and is popular with residents of the greater Paris area as a walking route and a spot for observing local wildlife. The reserve's character — an extensive, quiet deciduous forest with pockets of old-growth trees — makes it an appealing destination for anyone seeking nature close to the Paris metropolitan area, though as a protected site it requires visitors to respect the rules that apply to ONF-managed conservation areas.

Frequently asked questions

What is the difference between a directed and an integral biological reserve? A directed reserve, like Pont Granval, involves active forest management by the ONF oriented toward conservation goals, unlike an integral reserve, where human intervention is kept to a strict minimum and the forest is left to natural succession.

How large is the Pont Granval reserve? The protected area covers 32.86 hectares within the Forêt de Marly.

Since when has this protection existed? The reserve was established on 7 December 1988.

What wildlife can be found here? The area is home to roe deer and wild boar, species typical of the large forest complexes of Île-de-France.

How do you get to Pont Granval from Paris? The Forêt de Marly, where the reserve is located, lies about 15 km west of Paris, between Saint-Germain-en-Laye and Versailles, near the communes of Saint-Benoît and Auffargis.