This linear trail runs along the northern and southern slopes of the Serra da Arrábida to Portinho da Arrábida, passing through the highest point of the mountain range, Alto do Formosinho, marked by a triangulation point at 501 m. This route, which is more challenging, most closely resembles mountaineering conditions due to its steep incline and the nature of the terrain. It is one of the region’s most iconic trails, due to its connection to the earliest settlements in Arrábida (the Castelo dos Mouros rock formation) and to the ancient pilgrimages in devotion to Our Lady of Arrábida, which continue to this day because of the challenge of reaching the summit—through dense vegetation, gravelly areas, and rock-climbing sections— as well as by the endless landscapes that connect the Sado estuary to the Tagus estuary and to the Finisterre border with the ocean. Located along the edge of the total protection zone of the Arrábida Natural Park, it stands out for its Mediterranean vegetation—characterized by dense, scrub-like growth—and for the rugged, unspoiled nature of the landscape.Toward the end of the route, we come to the Convent of Arrábida, located on the southern slope of the Arrábida Mountains, which dates back to the 16th century. Nearby, there are several watchtowers, the Bom Jesus Chapel, and the Old Convent, all of which are worth a visit. The park is owned by the Oriente Foundation, so visits must be booked in advance.