A megacity is a very large city, typically with a population of more than 10 million people. The United Nations Department of Economic and Social Affairs in its 2018 "World Urbanization Prospects" report defines megacities as urban agglomerations with over 10 million inhabitants. A University of Bonn report holds that they are "usually defined as metropolitan areas with a total population of 10 million or more people". Elsewhere in other sources, from five to eight million is considered the minimum threshold, alongside a population density of at least 2,000 per square kilometre. The terms conurbation, metropolis, and metroplex are also applied to the latter.
A metropolitan area or metro is a region consisting of a densely populated urban agglomeration and its surrounding territories sharing industries, commercial areas, transport network, infrastructures and housing. A metropolitan area usually comprises multiple principal cities, jurisdictions and municipalities: neighborhoods, townships, boroughs, cities, towns, exurbs, suburbs, counties, districts and even states and nations in areas like the eurodistricts. As social, economic and political institutions have changed, metropolitan areas have become key economic and political regions.
Tourcoing is a city in northern France on the Belgian border. It is designated municipally as a commune within the department of Nord. Located to the north-northeast of Lille, adjacent to Roubaix, Tourcoing is the chef-lieu of two cantons and the fourth largest city in the French region of Hauts-de-France ranked by population with about 97,000 inhabitants.
The commune is a level of administrative division in the French Republic. French communes are analogous to civil townships and incorporated municipalities in the United States and Canada, Gemeinden in Germany, comuni in Italy, or municipios in Spain. The UK equivalent are civil parishes. Communes are based on historical geographic communities or villages and are vested with significant powers to manage the populations and land of the geographic area covered. The communes are the fourth-level administrative divisions of France.
An aire urbaine is an INSEE statistical concept describing a core of urban development and the extent of its commuter activity. It was replaced by the concept "functional area", which uses the same definition as Eurostat's functional urban areas, in 2020.
An urban area, built-up area or urban agglomeration is a human settlement with a high population density and an infrastructure of built environment. This is the core of a metropolitan statistical area in the United States, if it contains a population of more than 50,000.
The city of Paris had a population of 2,165,423 people within its administrative city limits as of January 1, 2019. It is surrounded by the Paris unité urbaine, or urban area, the most populous urban area in the European Union. In 2018 the unité urbaine had a population of 10,816,803 in 2,854 km2 (1,102 sq mi). The Paris Region, or Île-de-France, covers 12,012 km2 (4,638 sq mi), and has its own regional council and president. It has a population of 12,213,447 as of January 2018, or 18.3 percent of the population of France. The metropolitan or functional area of Paris covers 18,941 km2 (7,313 sq mi) and has 13,064,617 inhabitants (2018).
The Flemish Diamond is the Flemish reference to a network of four metropolitan areas in Belgium, three of which are in the central provinces of Flanders, together with the Brussels-Capital Region. It consists of four agglomerations which form the four corners of an abstract diamond shape: Brussels, Ghent, Antwerp and Leuven.
The larger urban zone (LUZ), or functional urban area (FUA), is a measure of the population and expanse of metropolitan and surrounding areas which may or may not be exclusively urban. It consists of a city and its commuting zone outside it.
The Blue Banana, also known as the European Megalopolis or the Liverpool–Milan Axis, is a discontinuous corridor of urbanization in Western and Central Europe, with a population of around 100 million. The conceptualisation of the area as a "Blue Banana" was developed in 1989 by RECLUS, a group of French geographers managed by Roger Brunet.
A metropolis is a large city or conurbation which is a significant economic, political, and cultural area for a country or region, and an important hub for regional or international connections, commerce, and communications.
The Katowice urban area, also known as the Upper Silesian urban area, is an urban area/conurbation in southern Poland, centered on Katowice. It is located in the Silesian Voivodeship and in a small part of the Lesser Poland Voivodeship. The Katowice urban area is the largest urban area in Poland and 21st largest urban area in the European Union. According to Demographia, its population is 1,903,000.
A metropolitan area is generally defined as consisting of an urban area, conurbation or agglomeration, together with the surrounding area to which it is closely economically and socially integrated through commuting.
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