Vallès Occidental

Vallès Occidental is a comarca in Catalonia, Spain. Sabadell and Terrassa are the comarcal capitals. Along with Vallès Oriental it forms the grand comarca of Vallès.

Vallès Occidental borders the comarques of Bages , Vallès Oriental , Baix Llobregat , and Barcelonès . It centers on the Catalan prelittoral depression, limited to the west by the River Llobregat and to the east by the River Caldes. The northern part of the comarca is mountainous. From west to east, it contains part of the Obac range ; the massifs of Sant Llorenç de Munt and Puig de la Creu ; and the Sant Sadurní and Farell cliffs . At the south of the comarca is the Collserola range , which forms part of the Catalan Littoral. Between these various ranges is the valley that gives its name to the comarca.
The valley actually composes two separate watersheds, the basins of the Llobregat and Besòs.

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