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Vallès Occidental borders the comarques of Bages (to the north), Vallès Oriental (to the north and east), Baix Llobregat (to the west), and Barcelonès (to the south). 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 (924m altitude at Castellsapera); the massifs of Sant Llorenç de Munt (1095m at La Mola and 1053m at Montcau) and Puig de la Creu (664m); and the Sant Sadurní (954m) and Farell cliffs (789m). At the south of the comarca is the Collserola range (512m), 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.
Industry is concentrated in the south, coinciding with the flattest land in the comarca. The principal industrial cities are the co-capitals Sabadell and Terrassa, as well as Rubí and Cerdanyola del Vallès. The most important industries are textiles, mechanical engineering, metallurgy, machinery, electrical equipment, construction, chemicals, paper, and the processing of food products. An industrial crisis at the end of the 1970s and the beginning of the 1980s led to a greater importance for the commercial and service sectors, especially computer-related work.
The north remains primarily rural. Many of the residences there now function as second homes.
Much of Catalonia's transportation network passes through Vallès Occidental, with roads, railroads, etc. crossing the valley in various directions.
Motorways
AP-7 crosses Vallès in an east-west direction. Heading west, it connects Vallès with Tarragona, València and the southern part of the Iberian Peninsula, similarly to the A-2/AP-2 (which connects Barcelona, Lleida, and Zaragoza). Heading east, it connects Vallès with the province of Girona and with France.
C-1413 starts at Molins de Rei, connects to the N-II and N-340 and the motorway A-2, and passes through Rubí, Sabadell, and Sentmenat before connecting finally to the N-152 at the heights of Centelles.
Both railroad companies that operate in Catalonia have lines in Vallès Occidental. Renfe's Barcelona-Lleida line passes through Manresa.
The Ferrocarrils de la Generalitat de Catalunya have the "Metro del Vallès", connecting Barcelona to Sabadell and Terrassa.
Airports
Most air traffic for Vallès Occidental comes through Prat airport in neighboring Baix Llobregat. Sabadell Airport is used for sport flying, as a base for firemen, and for air freight.
Politics and government
Comarcal council
Councilors in the Comarcal Council of Vallès Occidental since 1987
Spain
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Barcelona
Vallès Occidental
