Castelo dos Mouros

Built by the Moors in the 8th-9th centuries to control the approach to Lisbon, this hilltop fortress was largely abandoned after the Christian Reconquista and restored in the 19th century under King Ferdinand II. Its battlements zigzag along the granite ridge above Sintra town, and walking the walls gives an open view down over the historic centre and the National Palace's twin chimneys, across to the Pena Palace on the next peak, and on clear days out to the Atlantic coast.