The Castle continued to be the seat of the Portuguese royal court until the 16th century following unification with Spain in 1580. After the restoration of the Portuguese state, the site took on a more military role which continued right up to the 20th century. Classified as National Monument in 1918.
The statue of Afonso Henriques, presented by the city of Porto, was installed on the 25th of October 1947 during restoration work of the site. On the 22nd of August 2006, Direcção Regional de Cultura Lisboa (DRCLisboa) defined a special protection zone, that included the Castle of São Jorge and the rest of the walls of Lisbon.