The plain of Barcelona is a plain located in the county of Barcelonès, in Catalonia, Spain. It borders the Mediterranean Sea, the Serra de Collserola mountain range, and the river deltas of the Llobregat and Besòs. Its geographical location is between 41° 16' and 41° 30' north latitude and between 1° 54' and 2° 18' east longitude. With a surface area of 102.16 km², the plain is about 11 km long and 6 km wide.