The valley marks the boundary between Lannion and Trébeurden and is flanked by Pors Mabo and Beg Léguer cliffs. The valley is home to one of the rare dune ranges in this area. Further back is wetland with various plant species that are quite rare in the department. The 47 hectares were once used for basic farming, subsequently abandoned owing to the difficult terrain. To save the landscape, extensive grazing has been established and today a variety of animals graze the restored meadowland. Note St Thurien chapel, known as the 'forgotten chapel', just off the GR34 hiking trail.