Barcelona is a city on the coast of northeastern Spain. It 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 numerous neighbouring municipalities within the Province of Barcelona and is home to around 4.8 million people, making it the fifth most populous urban area in the European Union after Paris, the Ruhr area, Madrid, and Milan

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 and the main economic and administrative centre of the Crown, only to be overtaken by Valencia, wrested from Arab domination by the Catalans, shortly before the dynastic union between the Crown of Castile and the Crown of Aragon in 1492.

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