Serra da Sintra Ridge Walk (Pena to Castelo dos Mouros)

The Serra da Sintra Ridge Walk links Pena Palace to the ruined Moorish Castle (Castelo dos Mouros) along a compact 4 km loop through the hills above Sintra, Portugal. The route begins at the Pena Palace ticket gate on Estrada da Pena, reached by Bus 434 from Sintra train station (a 40-minute ride from Lisbon Rossio); no separate hiking permit is needed, though entry tickets are required for the palace grounds themselves. Total ascent is roughly 200 m, with the highest point around 528 m at the Pena Palace terrace, making this a short but occasionally steep climb over cobbled and rocky mule paths. Surfaces alternate between polished cobblestone near the palace and loose granite scree along the exposed granite outcrops of the Moorish Castle walls, so grip can be tricky in wet weather. Shade from the Sintra Mountains' subtropical forest cover is generous for most of the route, offering welcome relief from summer sun. Key landmarks include the High Cross viewpoint at Castelo dos Mouros, the fern-lined switchbacks connecting the two sites, and sweeping views over Sintra town and the Atlantic on clear days. Hikers who prefer a shorter outing can turn around at the High Cross viewpoint, roughly the midpoint, cutting the walk to about 2 km. There are no water sources or shelters directly on the trail, though cafes cluster near both the Pena Palace and Moorish Castle entrances. Because both endpoints are ticketed heritage sites, most walkers pair the hike with a visit to the palace interior or castle ramparts rather than treating it as a standalone hike.