|Perched on the city´s highest point, Portalegre Castle is proof of the position´s strategic importance so close to Spain. With little prior documentation surviving, it is known that the defensive system was overhauled by king Dinis, at the end of the 13th and the beginning of the 14th century when the city again became a royal possession.
It was made up of the inner courtyard and a double wall with twelve towers and seven gates. Remaining of those walls there are what are now the Alegrete, Crato (near the Se) and Devesa Gateways. The remaining parts have been swallowed up by the city. Tile panels mark the locations of the former entranceways into the city.
In the 17th century, the towers were altered to house artillery weaponry, remaining in military service through to the 19th century. At the beginning of the 20th century, extending Rua do Castelo forced the demolition of one part of the castle walls. The inner courtyard was thus cut into two: on one side there are two towers and gardens and, on the other, the Keep, housing the city´s museum.
On the first floor there is a room whose arches form the coat of arms of king Manuel, in commemoration of his feats in Portalegre.