The walk crosses the ‘Abannets’ plateau. Its chasms dug into the chalk guide you to ‘falcon rock’ and its vista over the village of Olloy-sur-Viroin. In the distance, the valleys of the Calestienne turn into the Ardennes forests. The rest of the route takes you to the ‘Fondry des Chiens’, whose chasm can reach up to 20 metres deep. Nearby, rare and delicate vegetation has developed on a chalk soil. On your return to the village, the ‘Maticolo’, a chasm above the course of the Eau Noire, forms a funnel-shaped cave that used to be covered in iron ore.

• Picnic area
• Parking
• Orientation table