Paris is the capital and largest city of France, with an estimated city population of 2.04 million in an area of 105.4 km2 (40.7 sq mi), and a metropolitan population of 13.2 million as of January 2026. Located on the river Seine in the centre of the Île-de-France region, it is the largest metropolitan area and fourth-most populous city in the European Union (EU). Nicknamed the "City of Light", partly because of its role in the Age of Enlightenment, Paris has been one of the world's major centres of finance, diplomacy, commerce, culture, fashion, and gastronomy since the 17th century. Administratively, Paris is divided into twenty arrondissements (districts), each having their own cultural identity. Haussmann's renovation of Paris, which created new boulevards, parks, and public works, gave birth to a modern city known as the "capital of the 19th century". Paris is a major railway, motorway, and air-transport hub; in 2024 Charles de Gaulle Airport was the EU's busiest airport. Paris has one of the most sustainable transportation systems in the world and is one of only two cities that have received the Sustainable Transport Award twice. Its Art Nouveau-decorated Métro has become a symbol of the city. Paris is known for its museums and architectural landmarks: the Musée d'Orsay, Musée Marmottan Monet, and Musée de l'Orangerie are noted for their collections of French Impressionist art, while the Musée National d'Art Moderne, Musée Rodin, and Musée Picasso are noted for their collections of modern and contemporary art. Parts of the city along the Seine have been designated as a UNESCO World Heritage Site since 1991.