Start from the southernmost access point of Goulien Beach.
(S/E) Take the path on the left that climbs the cliff at the end of the beach. It follows the edge of the cliff and climbs up the slope, bypassing a collapsed section. When you reach the first pine trees, the path passes right next to an isolated tree with a particularly twisted stump.
(1) At the intersection that appears immediately, continue along the coastal path, which soon reaches the first coves. Although the beaches look inviting, they are not easy to reach. So we will content ourselves with admiring them from above. After coming to a path that descends through the moorland, the trail climbs back up to skirt around a first headland. Descending, turn right to reach a viewpoint that has been built above the drop.
(2) To the right at the foot of the cliff, you can see one of the many arches that dot this rugged coastline. Others will follow, including the one that serves as a bridge to the Château de Dinan, which will appear as you continue along the path. Before reaching it, you can descend (at your own risk) along the path that skirts the point on the right, to take the vertiginous passage that leads to this fortress-like rock formation.
(3) At the point overlooking the site, turn left to reach its highest point. The view of the Iroise Sea is truly majestic, stretching from Cap de la Chèvre to Ouessant, visibility permitting. Descend along the path leading to the car park, overlooking Porzh Koubou Beach.
(4) Leave the car park by going up the small road that leads to it until you reach the hamlet of Kerguillé. Turn left at the first intersection and drive through the hamlet. A path continues along the road, which leads to meadows grazed by a flock of sheep. The path narrows as you venture further along it.
(5) Turn left at the first intersection to return closer to the coast.
After a wide curve to the right, you will come to a straight, flat section until you pass a grove of maritime pines on your right.
(6) When you reach the last trees of the grove, take the track that descends to the left, across the moor, to rejoin the coastal path near the twisted pine tree you saw on the way out.
(1) Then turn right to retrace the last few hundred metres in the opposite direction to the start (S/E).