Castle Penela is located on a hill and towers over the urban-type settlement of Penela. During the Reconquista, the castle was of great strategic importance, and acted as a fortress, protecting Coimbra. Castle Penela, like another famous castle of Montemor-o-Veljo, is an excellent example of defensive structures, which were built at the time.

The fortress covers an area of about 1, 23 acres and has the shape of an irregular polygon. The architecture combines amazing Gothic and Romanesque styles. During its existence of significant construction works in the castle were carried out twice. First time - in the XIV century, when it was built a new ring of walls with twelve towers. Unfortunately, only four towers have survived to our times. And the following additions were made in the fifteenth century – were built clock tower and rebuilt the donjon. The height of the walls varies from 7 to 19 meters.

It is assumed that the place on which is erected a castle, was previously inhabited by Roman tribes, who built a watchtower to guard the path connecting mérida, Conimbriga and Braga. However, there is no substantial evidence to support such a hypothesis, and that this fortification was built during the occupation by the Muslims in the twelfth century the Iberian Peninsula.

The fortress that we see today was built between the XIV-XVI centuries. In addition to the main gate, survived the other two gates of the fortress - Port da Vila (XV century) and the Port da Traicao. As a fortification, the fortress served until the eighteenth century. The great earthquake in 1755 destroyed the dungeon and one of the gates. Later the keep was restored.

By the XX century the old fortress was in full decline. The destruction of this scale historical monument attracted the attention of the public and in 1910 the castle was included in the list of monuments of national importance.