Barcelona (Catalan IPA: [bəɾsəˈlonə], Spanish IPA: [baɾθeˈlona]) is the most populous city of the Autonomous Community of Catalonia and the second largest city in Spain, with a population of 1,615,908 in 2008, while the population of the Metropolitan Area was 3,161,081. It is the central nucleus of the Urban Region of Barcelona, which relies on a population of about 5.5 million. It is located on the Mediterranean coast ( 41°23′N 2°11′E / 41.383°N 2.183°E) between the mouths of the rivers Llobregat and Besòs and is bounded to the west by the Serra de Collserola ridge (512 m/1,680 ft).