“An imposing monument, which dominates the historic centre of the town of Mértola, considered an invincible fortress for centuries.
Most of the building was built in the 13th century by the knights of the Order of Santiago, with a military structure and walled enclosure.
Its main element is the Castle Keep, almost 30 metres high, which currently houses a museum with a panoramic view over the historic area of Mértola and the Guadiana River.
Over the door is the following inscription “This keep was ordered to be made by Dom João Fernandes, the first master that there was in Portugal. It dates from 1330”.
In the mid-20th century, the ruins of the old castle were classified as a National Monument and repair works were subsequently carried out. Today, it is one of the town’s main attractions.”