The origins of Castell d'Aro can be found in the mediaeval castle of Benedormiens, which from 1041 watched over the monastery of Sant Feliu de Guíxols with the mission of protecting the Aro valley from looters who arrived by sea. Declared a Cultural Asset of National Interest by the Government of Catalonia in 1996, it is set on a small 42-metre hill, at the top of which stands Benedormiens castle. The castle was seriously damaged by an accidental explosion in 1879 but has since been partially restored and turned into an exhibition venue. The architecture of the houses includes elements from the 15th to the 18th centuries, while the church of Santa Maria is of Gothic construction with baroque elements. It has been declared a Cultural Asset of National Interest.