Otherwise known as the Castelo do Queijo (Cheese Castle) because of the wedge of rock it stands upon, Forte de São Francisco Xavier looks every inch the archetypal fortress, with its sturdy ramparts, watchtowers and drawbridge. Built in 1661, it harbours a small weaponry exhibition, but more impressive is the view reaching out to sea – sunset is prime time.
Forte de São Francisco Xavier
Foz do Douro