During the 19th century the Castle of Rocha Forte underwent a systematic plundering and treasure hunters left their mark in the old ruins, but there were also scholars who paid attention to the castle. Jesuit priest Celestino García Romero wrote in 1920: [The bridge of Amañecida], perhaps destroyed by a flood or any such accident, some of our archbishops had it extended and repaired in order to connect the city with the castle of A Rocha which used to stand nearby and of which only ruins have survived. There I collected scraps of fabric with pictures years ago.
A scientific archaeology made an appearance in Rocha Forte in the 1930s. It did not focus on the castle, but on quite a different heritage asset: the petroglyph of Castriño de Conxo, found and registered in 1935 by Ramón Sobrino and his son. The Committee of the Archaeological Museum of Santiago had discussed the idea of conducting explorations in a number of locations in Galicia, including the castle’s site, several times. But the proposal was on hold until solving the issue of the ownership of the land, which was in dispute.
After that, it went back into oblivion while heritage aggressions against the old fortress continued. In 1962, the electricity utility company FENOSA installed a high voltage electricity pylon right in the middle of the ruins. According to newspaper El Pueblo Gallego, the workers laying the foundations for the structure had discovered a true buried treasure, a vaulted staircase and an underground passage buried four metres down. On 15 September 1873 opens the railway line connecting Cornes and Carril, which crossed part of the site and used part of the foundations of the old castle to support the new railway line.