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, along with 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 which share 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.
Greater Buenos Aires, also known as the Buenos Aires Metropolitan Area, refers to the urban agglomeration comprising the Autonomous City of Buenos Aires and the adjacent 24 partidos (districts) in the Province of Buenos Aires. Thus, it does not constitute a single administrative unit. The conurbation spreads south, west and north of Buenos Aires city. To the east, the River Plate serves as a natural boundary.
An urban area 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 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 Madrid metropolitan area is a monocentric metropolitan area in the centre of the Iberian peninsula, around the municipality of Madrid, Spain. It is not related to any sort of administrative delimitation, and thus, its limits are ambiguous.
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. Over time, the region has been referred to by several names, each reflecting its development and significance. Initially, French geographer Roger Brunet, as the leader of RECLUS, described the area as 'the European Backbone', which depicted an urban corridor extending from Liverpool to Milan. Characterized by significant industrialization and urbanization, this area has attracted numerous public and private enterprises since the early post-war period, prompting researchers and academics to investigate the factors behind its remarkable development within Europe. It stretches approximately from North West England through the English Midlands across Greater London to the European Metropolis of Lille, the Benelux states with the Dutch Randstad and Brussels and along the German Rhineland, Southern Germany, Alsace-Moselle in France in the west and Switzerland to Northern Italy in the south.
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. The Katowice urban area is the largest urban area in Poland and 22nd largest urban area in the European Union. According to Demographia, its population is 1,903,000.
A 2001 ESPON metropolitan area was defined as consisting of an urban area, conurbation or agglomeration, together with the surrounding area to which it was closely economically and socially integrated through commuting.
In January 2020, the municipality of Madrid, capital of Spain, had a population of 3,345,894 registered inhabitants in an area of 604.3 square kilometers (233.3 sq mi). Thus, the city's population density was about 5,337 inhabitants per km2. Madrid is Spain's largest city and the second most populous city proper in the European Union, after Berlin.
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