3 Best Sights in Northern Portugal, Portugal

This castle was built (or at least reconstructed from earlier remains) in the 11th century by Henry of Burgundy; his son, Afonso Henriques, was born within its great battlements and flanking towers. Standing high on a solid rock base above the town, the castle has been superbly preserved. A path leads down from its walls to the tiny Romanesque Capela de São Miguel, the chapel traditionally said to be where Afonso Henriques was baptized—in fact it was built well after his death, although the baptismal font may be older. The ticket office is in the neighboring Paço dos Duques, former palace of the Dukes of Bragança, which may also be visited. It was built in the 15th century but has been irretrievably altered; in 1959 it became the official residence in the North of Portugal's president, but is normally open to the public, with impressive displays of tapestries, furniture, ceramics, paintings and weapons.

The great ramparts of this 16th-century fortification added the words do castelo to the town's name and protected it against attack from pirates eager to share in its wealth. It was completed during the reign of King Manuel I, which is why architectural details such as the Roqueta Tower are Manueline in style. These days the massive structure serves as a hotel, among other uses. A large market is held outside the castle walls every Friday.

The city's most prominent landmark is this great, blunt, 14th-century castle keep overlooking the river. It houses the military collection of the Museu da Região Flaviense (Flaviense Regional Museum), where a hodgepodge of local archeological finds are presented in a free display at the neighboring city hall. The ramparts around the tower offer grand views of the town.