Paris is the capital and most populous city of France. It has an area of 105 square kilometres (41 square miles) and a population of 2,229,621 in 2015 within its administrative limits. The city is both a commune and department and forms the centre and headquarters of the Île-de-France, or Paris Region, which has an area of 12,012 square kilometres (4,638 square miles) and a population in 2016 of 12,142,802, comprising roughly 18 percent of the population of France. By the 17th century, Paris was one of Europe's major centres of finance, commerce, fashion, science, and the arts, and it retains that position still today. The Paris Region had a GDP of €624 billion (US $687 billion) in 2012, accounting for 30.0 percent of the GDP of France.
The City of Paris is but the core of a built-up area that extends well beyond its administrative limits. Commonly referred to as the agglomération Parisienne, and statistically as a unité urbaine (a measure of urban area), the agglomeration has a 2013 population of 10,601,122, which makes it the largest in the European Union. City-influenced commuter activity reaches well beyond even this in a statistical aire urbaine de Paris (a measure of metropolitan area), that had a 2013 population of 12,405,426, a number one-fifth the population of France, and one that makes it, after London, the second largest metropolitan area in the European Union. Although joined in a single urban tissue, Paris' lack of administrative and economic cohesion with its suburbs has been a longstanding problem, but a 2016 'Metropole of Grand Paris' economic and environmental initiative covering an 814 square kilometres (314 square miles) area and a population of 7 million, exists since 2016