Ripoll River through the Vallès Nature · Sabadell, Vallès Occidental, Barcelona The Ripoll rises in the sot del Galí, in the Serra de Granera, at 640 metres above sea level, within the municipality of Sant Llorenç Savall, and runs for 39.2 kilometres until it joins the Besòs at Montcada i Reixac, passing through Sant Feliu del Racó, Castellar del Vallès, Sabadell, Barberà del Vallès and Ripollet. Along its course it powered flour mills for centuries which, from the 18th century onwards, were gradually converted into paper mills, and in the 20th century it saw strong growth in textile businesses that seriously polluted its waters. On 25 September 1962 a torrential rainfall of 225 litres per square metre caused a catastrophic flood that left close to a thousand dead in the Vallès Occidental. Photo: Viquipèdia / Wikimedia Commons (CC BY-SA) What to see and do in Sabadell