The most interesting things to visit are mainly inside the fortress that looks down to the Minho River and Spain. They have been destroyed several times whether it were the Barbarians, the Arabs, the armies of Asturias and Leon or even the French troops in the 19th century, they have always been restored and still very well preserved. Valença’s fortress is a piece of gothic and baroque military architecture. The first walls were built in the 13th century. It was upgraded during the 17th and 18th century forming the present bulwarked system. It is placed on top of two small hills and it is formed by two polygons (the Recinto Magistral and the Coroada) separated by a ditch and with four doors (Coroada, Gaviarra, Fonte da Vila and Sol). The main entrance is Porta do Sol (Sun’s door). This door was damaged during the Napoleonic invasions.