Barcelona is the capital and largest city of the autonomous community of Catalonia, as well as the second most populous municipality of Spain. With a population of 1.6 million within city limits, its urban area extends to around 4.8 million people, making it the fifth most populous urban area in the European Union. It is located on the coast between the mouths of the rivers Llobregat and Besòs, and bounded to the west by the Serra de Collserola mountain range, the tallest peak of which is 512 metres (1,680 feet) high.
Founded as a Roman city, in the Middle Ages Barcelona became the capital of the County of Barcelona. After joining with the Kingdom of Aragon to form the confederation of the Crown of Aragon, Barcelona, which continued to be the capital of the Principality of Catalonia, became the most important city in the Crown of Aragon. Barcelona has a rich cultural heritage and is today an important cultural centre and a major tourist destination. Particularly renowned are the architectural works of Antoni Gaudí and Lluís Domènech i Montaner, which have been designated UNESCO World Heritage Sites.