Rocha Forte is the local version of a type of fortress known as concentric castle, designed by French crusaders to control the territory conquered in the Holy Land. Following this model, it adds and strengthens such defensive elements as concentric walls or the ward and the division of space between the walls.
After the first urban revolt against Archbishop Berenguel de Landoira, this prelate decided to rebuild and strengthen the castle to consolidate his power in the area of Santiago de Compostela. Berenguel strengthened the military architecture with a new configuration, altering the building commissioned by Xoán Arias and after the most innovative trends in the Europe of the time.
The alterations by Berenguel de Landoira in the 14th century gave the castle the shape we see today: a monumental enclosure with nine towers and a yet to be determined number of outer walls or fences. Within them, the documentation mentions the existence of a number of houses and households, amounting to a small village. Successive alterations adapted the caste to the new defensive needs brought about by the irruption of artillery, such as the construction of the lower outer rampant or barbican.