A day on foot across the Serra de Collserola, the wooded range that separates Barcelona from the Vallès plain, on an indicative route of about 13.9 km, nine tenths of it on paths and forest tracks. It starts at the Baixador de Vallvidrera station, a short train ride from the city centre, and climbs about 270 metres through the forest, by the Turó d'en Ferrer, to the temple of the Sagrat Cor, on the summit of Tibidabo. From there everything goes down: a forgotten viaduct in the forest, the Romanesque hermitage of Sant Medir, the Can Borrell farmhouse and, at the end of the valley, the monastery of Sant Cugat and its cloister. The train at Sant Cugat Centre closes the day. A little under four hours of walking, without the visits.