Although many archaeological sites have been lost in the Serra due to the powerful influence exercised by the conurbation of Barcelona through the construction of communications, residential establishments, etc., the ruins of Iberian villages, a series of remains from the Roman period and Gothic high windows and restoration elements are amongst the historic heritage that has been conserved in Collserola to the present day.
Particularly important are the Romanesque remains in the Park, both due to their number (more than thirty buildings listed as such) and their historic interest and value. Nor should we forget the Art Nouveau sites, dating to around the turn of the 20th century, that are found in the Park.