Comprised of several hills that separate the Vallès Oriental plain from the Maresme coastline, this park is divided into three mountainous areas: La Conreria, Sant Mateu and Céllecs.
The good climate and strategic location led to the settlement of man in the area from time immemorial. The oldest signs dates back to Neolithic times and the first communities are of Iberian Laietani origin and later Roman. The archaeological remains live alongside masias and medieval buildings, a reminder of the feudal and agricultural past that has characterised the area for centuries.
Currently the park includes fourteen towns and villages: Alella, Argentona, Cabrera de Mar, Cabrils, La Roca del Vallès, Martorelles, Montornès del Vallès, Premià de Dalt, Santa Maria de Martorelles, Teià, Tiana, Vallromanes, Vilanova del Vallès and Vilassar de Dalt. The area acts as an ecological lung for the whole region.
The rounded hills characterise this mountain range, such as those of Céllecs, Montcabrer and Burriac. The landscape today shows the large human footprint on this natural environment, with cultivated lands and inhabited areas that today are predominantly housing developments.
Throughout the park there are various walking itineraries, such as the Toni rock (which goes through Cabrils and Vilassar de Dalt), the route of the esquirol (blackleg) in Premià de Dalt or the cross of Montcabrer in Cabrils. It is also possible to go through several towns by bike following the marine route, or to follow one of the three bird watching itineraries that the park organises, in Cabrera de Mar.