Go to Sorède to park in the large shaded car park at the Vallée des Tortues animal park (signposted route). You can move away from the park entrance to find shade further away, to the north-west.
(S/E) From the main entrance, head north-west to the edge of the park (fence on the right). Turn right at the meadow and head down towards the River Sorède (Ribera de Sureda). Follow the river (on your right) and turn left until you reach the outskirts of Sorède via Rue du Mas Soula.
(1) Before a left-hand bend, leave this street and turn right onto a well-marked path that crosses the Rivière de Sorède below and climbs up to Rue du Mas Félix. Head north, continuing straight on, until you reach the second intersection.
(2) Turn right onto Traverse de Notre-Dame du Château.
Follow it until the junction with Rue de Notre-Dame d'Ultrera. Then turn right and continue to the edge of the residential area. There, turn left onto a well-marked path that runs alongside the housing estate (guide on the left).
(3) At the junction with Rue du Mas del Rost, turn right onto the tarmac road that leaves the built-up area to the east. Take the shortcut straight ahead rather than following the winding road. Further on, after the last houses on the left, you will come to a large crossroads.
(4) Turn right to head south. Continue along this DFCI AL27 track, ignoring any side paths. Further on, you will come to a crossroads with yellow directional signs.
(5) Continue straight ahead on the same track to descend to the hamlet of La Pave (la Pava). At the crossroads of tracks at the entrance to the hamlet, turn right to reach the Sant Ferriol de la Pava Chapel. Walk around it. Old fountain nearby
(6) Retrace your steps and head west along a marked path.
(5) Back at the crossroads, continue straight ahead, slightly to the right, towards the Hermitage of Notre-Dame du Château (signposted). The steady climb is along a rocky path. Beautiful views of the coastline (Argelès, Saint-Cyprien, Canet). Arrive at a fountain restored in July 1952 with a huge rock nearby. Follow the signs to the left of the water source. As you climb the marked trail to Puig de Sant Miquel, enjoy views of the coastline, the Roussillon plain and the hinterland, not to mention the Corbières and the Canigou Massif. You will arrive at the flat area of Castrum du Castell d'Ultrera.
(7) Please note: in bad weather or after rain, keep to the right on the marked path.
Leave the yellow markings and turn left to go around the rocky outcrop dominated by the castle ruins. At the start, the path is more or less visible among the outcropping rocks. There is then a series of ascents and descents until you reach a crossroads. Go up to the right towards a ruined wall. The entrance is through a gap in this wall. Immediately after, turn right to continue climbing (wall on the right). Turn left to cross the metal ladder. You will arrive at the highest point of Castell d'Ultera.
(8) Caution: take care at the start of this path, which is a ledge overlooking the void. Stroll at your leisure among the ruins, which offer magnificent 360° views. Retrace your steps, climb the ladder and wall to exit through the gap and descend to the crossroads. Turn right to continue around the hill. Keep close to the rock. Further on, the path moves away from the rock face as it descends. On the left, there is a huge rock resting on top of others. You will arrive in the undergrowth. There is a natural shelter at the foot of the rock face. Shortly afterwards, the path climbs up to the right and comes to a fence just before a visible crossroads, at an altitude of 497 m. Turn left and walk about ten metres along the fence to find a path leading to the former site of the Himalaya solar oven. View of the rocky spur of the Château. Retrace your steps to the crossroads at an altitude of 497 m and descend to the left to reach the Hermitage of Notre-Dame du Château via the rocky path.
(9) You can visit the Chapel of the Hermitage of Notre Dame du Château (Mare de Déu del Castell) and have a picnic in the shade (furnished area). See the fresco of the Procession dating from 1938. Descend a few metres to reach the track below the hermitage. Head west towards the Chapel of Christ (Capella del Crist), on the right along the track. Continue to a fork in the track.
(10) Keep left along this downhill DFCI track, which passes a junction of marked tracks in front of a cistern until it bends to the left.
(11) Leave the track and take a visible, well-trodden path that serves as a shortcut. It crosses the DFCI track four times. Thefifth time, turn right onto the track and continue. After several hairpin bends, you will come out onto the road to La Vallée Heureuse (Rue de La Farga).
(12) Turn right and walk carefully along this street, passing over the Pont de la Resclosa bridge until you return to the car park of the Vallée des Tortues animal park (S/E).
Very beautiful hike, but from point 7 onwards, the entire elevation gain is there. The climb is very difficult, a small V-shaped path eroded by rain. We did not climb up to the castle ruins, but passed underneath them and had a snack at the N-D du Château hermitage. There are two water taps: the one on the left is not drinkable, but there is nothing on the right. I filled my water bottle and did not get sick. The rest of the route was fine.