This article contains too many pictures, charts or diagrams for its overall length.
This article needs additional citations for verification. (April 2021)
A metropolis ( //)  is a large city or conurbation which is a significant economic, political, and cultural center for a country or region, and an important hub for regional or international connections, commerce, and communications. The term is Ancient Greek (μητρόπολις) and means the "mother city" of a colony (in the ancient sense), that is, the city which sent out settlers. This was later generalized to a city regarded as a center of a specified activity, or any large, important city in a nation.
A big city belonging to a larger urban agglomeration, but which is not the core of that agglomeration, is not generally considered a metropolis but a part of it. The plural of the word is metropolises,  although the Latin plural is metropoles, from the Greek metropoleis (μητρoπόλεις).
For urban centers outside metropolitan areas that generate a similar attraction on a smaller scale for their region, the concept of the regiopolis ("regio" for short) was introduced by urban and regional planning researchers in Germany in 2006. 
Metropolis (μητρόπολις) is a Greek word, coming from μήτηρ, mḗtēr meaning "mother" and πόλις, pólis meaning "city" or "town", which is how the Greek colonies of antiquity referred to their original cities, with whom they retained cultic and political-cultural connections. The word was used in post-classical Latin for the chief city of a province, the seat of the government and, in particular, ecclesiastically for the seat or see of a metropolitan bishop to whom suffragan bishops were responsible.  This usage equates the province with the diocese or episcopal see. 
Luanda is the capital and largest city in Angola. It is Angola's primary port, and its major industrial, cultural and urban centre. Its metropolitan area is the most populous Portuguese-speaking capital city in the world, with over 8.3 million inhabitants. 
Kinshasa is a megacity with a population of about 15 million. Kinshasa is Africa's third-largest urban area after Cairo and Lagos.  It is projected to be one of the ten biggest cities in the world in 2050. 
According to the 2014 census, Abidjan's population was 4.7 million, which is 20 percent of the overall population of the country, and this also makes it the sixth most populous city proper in Africa, after Lagos, Cairo, Kinshasa, Dar es Salaam, and Johannesburg. It has officially been designated as the "economic capital" of the country. In 2020 the Urban area population was over 5 million inhabitants. 
Lagos is projected to be one of the ten biggest cities in the world in 2050.  As of 2015, unofficial figures put the population of "Greater Metropolitan Lagos", which includes Lagos and its surrounding metro area, extending as far as into Ogun State, at approximately 21 million.  
With a population increase of 5.6 percent per year from 2002 to 2012, Dar es Salaam is the third-fastest-growing city in Africa, after Bamako and Lagos, and the ninth-fastest-growing in the world. The metro population is expected to reach 15.12 million by 2020.  
Kampala is the capital and largest city of Uganda. Kampala's metropolitan area is estimated at 6,709,900 people in 2019 by the Uganda Bureau of Statistics  in an area of 8,451.9 square kilometres (3,263.3 sq mi). Kampala is reported to be among the fastest-growing cities in Africa, with an annual population growth rate of 4.03 percent. 
In the People's Republic of Bangladesh, there are eleven metropolitan areas: Dhaka North, Dhaka South, Gazipur, Chittagong, Rajshahi, Khulna, Sylhet, Barisal, and Rangpur. Lands are highly priced and residents are considered to have a better urban lifestyle. Special police departments are allotted for the metropolitan cities, and there are city corporations for which mayors are elected for five-year regimes. Most of these cities have population density of 35,000/square mile or more. Dhaka is the wealthiest city out of all of them and is considered a Megacity because its population surpassed 10 million. 
China (People's Republic of China) is the fourth-largest country by geographical area and the most populous country with over 1.4 billion people and is also known for its large number of metropoles, with recognised "tiers" that classify mainland metropoles. Nationally, the largest metropoles include Hong Kong, Beijing, Shanghai, Guangzhou, and Shenzhen, the first four being the "First-Tier Cities" (一线城市). Second-tier cities are numerous and consist of regional centres, such as Changsha, Chengdu, Chongqing, Hangzhou, Jinan, Nanjing, Qingdao, Shenyang, Tianjin, Wuhan, and Xi'an, etc.
India (Republic of India) is the seventh-largest country by geographical area and the second-most populous country with over 1.3 billion people. The 74th Amendment to the Indian Constitution defines a metropolitan area as an area having a population of 10 Lakh or 1 Million or more, comprised in one or more districts and consisting of two or more Municipalities or Panchayats or other contiguous areas, specified by the Governor by public notification to be a Metropolitan area. The important metropolises in India are Ahmedabad, Bangalore, Chennai, Delhi, Hyderabad, Kochi, Kolkata, Mumbai, Patna, Pune, and Visakhapatnam.
In Indonesia, the metropolitan cities are in Jabodetabek ( Jakarta, Bekasi, Bogor, Depok, and Tangerang), the biggest metropolitan area in Southeast Asia and the fifth biggest metropolitan area in the world (2007). The other metropolises are Bandung, Medan, Semarang, and Surabaya.
The Japanese legal term to (都) is by designation to be translated as "metropolis".  however existing translations predate the designation. Structured like a prefecture instead of a normal city, there is only one to in Japan, namely Tokyo. As of 2020 [update], Japan has 12 other cities with populations greater than one million. The same Kanji character in Chinese, or in generic Japanese (traditional or non-specific), translates variously—city, municipality, special municipality—all qualify.
According to the census of 2017, there are about 12 metropolitan areas in Pakistan each with a metro population of at least 2 million and city proper population of at least 0.5 million.    Karachi is the largest metropolitan area of Pakistan with a population of about 16.01 million, followed by Lahore (11.12 million), Faisalabad (7.873 million), Islamabad-Rawalpindi (7.412 million), Gujranwala (5.01 million), Multan (4.745 million), Peshawar (4.269 million), Sargodha (3.903 million), Sialkot (3.893 million), Bahawalpur (3.668 million), Quetta (2.275 million) and Hyderabad (2.199 million). 
Metropolitan Manila, or Metro Manila, is the metropolitan region encompassing the city of Manila and its surrounding areas in the Philippines. It is composed of 17 cities namely Manila, Caloocan, Las Piñas, Makati, Malabon, Mandaluyong, Marikina, Muntinlupa, Navotas, Pasay, Pasig, Parañaque, Quezon City, San Juan, Taguig, Valenzuela and Pateros. The region is the political, economic, social, cultural, and educational center of the Philippines. As proclaimed by Presidential Decree No. 940, Metro Manila as a whole is the Philippines' seat of government but the city of Manila is the capital. The largest city in the metropolis is Quezon City, while the largest business district is the Makati Central Business District.
In the Republic of Korea there are seven special and metropolitan cities at autonomous administrative levels. These are the most populous metropolitan areas in the country. In decreasing order of the population of 2015 census, they are Seoul, Busan, Incheon, Daegu, Daejeon, Gwangju and Ulsan.
According to the census of 2015, cities of Changwon and Suwon also qualify for being elevated to the level of metropolitan cities (having population over 1 million), but any future plans to promote them into metropolitan city are unlikely to be accepted because of political concerns about the structure of administrative divisions. There are also some county-level cities with increasing population near 1 million, namely Goyang, Yongin, and Seongnam, but they are also unlikely to be promoted into metropolitan city because they are all satellite cities of Seoul.
Skyline of Taichung
Taipei City is the political, economic, and cultural centre of Taiwan. The Taipei–Keelung metropolitan area consists of 4 administrative divisions ( Taipei, Keelung, New Taipei, and Taoyuan) with a total of more than 9 million residents.  The metropolis houses the largest international airport in Taiwan and the 36th busiest airport in the world – Taiwan Taoyuan International Airport, which has an annual passenger traffic of nearly 50 million. 
Tashkent is Uzbekistan's most populous city and the only with over one million residents.
Vienna is the capital city of Austria, an old imperial city, and the seat of many international organisations, including OPEC, as well as hosting a main office of the United Nations. Together with its cultural acumen and history, these features make Vienna a true global metropolis, the only one in Austria.
Prague is the Czech Republic's only metropolis, with more than 1.3 million people living within the city limits and with more than 2.6 million living in its metropolitan area. This makes the Prague metropolitan area one of largest in Europe. 
Finland's capital, Helsinki, along with the neighboring areas (including Espoo, Kauniainen and Vantaa) forms a metropolitan area with an approximate population of 1.45 million people. This area is the only metropolis in the country.
France's national statistics institute, Insee, designates 12 of the country's urban areas as metropolitan areas. Paris, Lyon and Marseille are the biggest, the other nine being Toulouse, Lille, Bordeaux, Nice, Nantes, Strasbourg, Rennes, Grenoble and Montpellier. 
Berlin is Germany's largest city.
Rhine-Ruhr is Germany's largest metropolis (the photo shows Dortmund).
Frankfurt is one of Germany's most important cities.
The largest German city by administrative borders is Berlin, while Rhine-Ruhr is the largest metropolitan area (with more than 10 million people). The importance of a city is measured with three groups of indicators, also called metropolitan functions: The decision making and control function, the innovation and competition function, and the gateway function. These functions are seen as key domains for metropolitan regions in developing their performance.
In spatial planning, a metropolis is usually observed within its regional context, thus the focus is mainly set on the metropolitan regions. These regions can be mono central or multi central. Eleven metropolitan regions have been defined due to these indicators: Berlin-Brandenburg, Bremen-Oldenburg, Dresden-Halle-Leipzig, Frankfurt-Rhine-Main, Hamburg, Hannover-Braunschweig-Göttingen-Wolfsburg, Munich, Nuremberg, Rhine-Neckar, Rhine-Ruhr (with Cologne/Bonn), and Stuttgart. 
As of January 1, 2015, there are 14 "metropolitan cities" in Italy. Rome, Milan, Naples and other big cores have taken in urban zones from their surrounding areas and merged them into the new entities, which have been home for one out of three Italians. The provinces remained in the parts of the country not belonging to any Città Metropolitana. 
The Union of Polish Metropoles ( Polish: Unia Metropolii Polskich), established in 1990, is an organization of the largest cities in the country. Currently twelve cities are members of the organization, of which 11 have more than a quarter-million inhabitants. The largest metropolitan area in Poland, if ranked solely by the number of inhabitants, is the Silesian Metropolis (in fact a metroplex), with around 3 million inhabitants (5 million inhabitants in the Silesian metropolitan area), followed by Warsaw, with around 1.7 million inhabitants in the city proper and 3.1 million in the Warsaw metropolitan area. The Silesian Metropolis is an initiative of recent years attempting to unite a large conurbation into one official urban unit. Other Polish metropoles are Kraków, Łódź, Wrocław, Poznań, Tricity, Szczecin and Bydgoszcz.
Romania has one big metropolis, Bucharest with a population of around 2.5 million people. Other metropolitan areas with populations of about half a million people are Cluj-Napoca, Iași, Timișoara, Brașov, Constanța, Galați and Craiova.
Saint Petersburg, the cultural capital and the second-largest city
Yekaterinburg, the fourth-largest city in the country.
Moscow is the capital and largest city of Russia, with a population estimated at 12.4 million residents within the city limits,  while over 17 million residents in the urban area,  and over 20 million residents in the Moscow Metropolitan Area.  Moscow is among the world's largest cities, being the most populous city entirely within Europe, the most populous urban area in Europe,  the most populous metropolitan area in Europe,  and also the largest city by land area on the European continent.  Saint Petersburg, the cultural capital, is the second-largest city, with a population of roughly 5.4 million inhabitants.  Other major urban areas are Yekaterinburg, Novosibirsk, Kazan, Nizhny Novgorod, and Chelyabinsk.
Spain has around 15 metropolitan areas with a population greater than 500,000 people. The largest is Madrid, located in the center of the Iberian peninsula and its the seat of the government and the monarch of Spain, with a metropolitan area of almost 7 million people surpassing the limits of its own autonomous community and making it one of the largest of Europe; Barcelona is the second largest city of Spain its metropolitan area comprise 5.5 million people with its limits surpassing its own province, other large cities are Valencia, and Sevilla.
In the United Kingdom, the term the Metropolis was used to refer to London, or the London conurbation. The term is retained by the London police force, the Metropolitan Police Service (the "Met"). The chief officer of the Metropolitan Police is formally known as the Commissioner of Police of the Metropolis. Since 1974 six conurbations (outside London) have been known as metropolitan counties, each divided into metropolitan districts. Other conurbations in the United Kingdom are also sometimes considered to be metropolitan areas, most notably South Yorkshire (centred on the city of Sheffield), the West Midlands (centred on the city of Birmingham), West Yorkshire (centred on the city of Leeds), Merseyside (centred on the city of Liverpool), Greater Manchester and Greater Glasgow which make up the most densely populated areas in the British Isles outside London.
Canada's six largest metropoles are Toronto, Montreal, Vancouver, Ottawa, Calgary, and Edmonton. Statistics Canada defines a census metropolitan area as one or more adjacent municipalities situated around a major urban core where the urban core has a population of at least 100,000.  Canada's most populated metropole is the City of Toronto, with a population of 2.7 million and a metropolitan population of over 6 million people. It is also the heart of Canada's finance and banking industry.
Toronto is Canada's largest city.
Montreal is Canada's largest French-speaking city.
Vancouver is Canada's largest coastal city and most important port.
In Mexico, the term metropolis is used to refer to an urban area of economic, political, and cultural importance. Mexico City represents all three factors as it is the country's capital and financial center with 27 million people. Other metropolises are Monterrey and Guadalajara, both metropolitan areas with a population over 6,000,000 inhabitants.
In the United States, an incorporated area or group of areas having a population more than 50,000 is required to have a metropolitan planning organization in order to facilitate major infrastructure projects and to ensure financial solvency. Thus, a population of 50,000 or greater has been used as a de facto standard to define a metropolis in the United States. A similar definition is used by the United States Census Bureau. The bureau defines a Metropolitan Statistical Area as "at least one urbanized area of 50,000 or more inhabitants." The six largest metropolitan areas in the USA are New York, Los Angeles, Chicago, Dallas, Houston, and Washington, D.C., with New York being the largest.
The Government of Australia defines a metropolitan area as any statistical division or district with a population of more than 100,000.  According to this definition, there are currently 19 metropolitan areas in Australia, including every state capital. By population, the largest metropolitan area is Sydney (urban area population at 2020 Census of 5,367,206) and the smallest is Bendigo (urban area population at 2020 Census of 100,632). 
Sydney is Australia's largest metropolis.
Melbourne is Australia's second-largest metropolis.
Brisbane is Australia's third-largest metropolis.
Gold Coast is Australia's largest regional city.
In Argentina, Buenos Aires is the principal metropolis with a population of around fifteen and a half million.  The Greater Buenos Aires conurbation, which also includes several Buenos Aires Province districts, constitutes the third-largest conurbation in Latin America.  Buenos Aires is the main political, financial, industrial, commercial, and cultural hub of Argentina.
In Brazil, the Greater São Paulo is the principal metropolis with over 21 million inhabitants. In the larger cities, such as São Paulo and Rio de Janeiro (population 6.3 million), favelas (slums) grew up over decades as people migrated from rural areas in order to find work. The term used in Brazilian Portuguese for a metropolitan area is Região Metropolitana. Other metropolises in Brazil with more than one million inhabitants include: Belém, Belo Horizonte, Brasília, Campinas, Curitiba, Fortaleza, Goiânia, Maceió, Manaus, Porto Alegre, Recife, Salvador and São Luís.
The primary metropolis in Chile is its capital: the city of Santiago, with a population of 7 million, living across its metropolitan area. Santiago is the main political, financial, industrial, commercial, and cultural hub of Chile. The other two metropolises in the country are the conurbations of Valparaíso and Concepción with a population of nearly 1 million each.
In Colombia, Bogotá is the main metropolis with over 13 million inhabitants residing in its Metropolitan Area, which includes boroughs like Soacha, Mosquera, Cota, and Chía. The second metropolis in Colombia is Medellín, which includes such boroughs as Envigado, Itagüi, La Estrella, and Sabaneta. This metropolitan area is known for having the first and only Metro in Colombia, the Medellín Metro. Bogotá has the Transmilenio, a Rapid Transit Metro-bus system.
The Lima metropolitan area is Peru's capital and largest city with over 10 million inhabitants, more than one third of the total national population.
In France, Portugal, Spain, and the Netherlands, the word metropolis (métropole (Fr.) / metrópole (Port.) / metrópoli (Spa.) / metropool (Dutch)) designates the mainland part of a country situated on or close to the European mainland; in the case of France, this means France without its overseas departments. For Portugal and Spain during the Spanish Empire and Portuguese Empire period, the term was used to designate Portugal or Spain minus its colonies (the Ultramar). In France métropole can also be used to refer to a large urban agglomeration; for example, "La Métropole de Lyon" (the Lyon Metropolis).
- Keri Blakinger (March 8, 2016). "From Gotham to Metropolis: A look at NYC's best nicknames". Daily News. New York. Retrieved August 6, 2017.
- "Definition of Metropolis". Oxford Dictionaries. Retrieved March 2, 2016.
- "Definition of metropolis". Collins English Dictionary. Retrieved October 23, 2012.
- Prof. Dr. Iris Reuther (FG Stadt- und Regionalplanung, Universität Kassel): Presentation "Regiopole Rostock". December 11, 2008. Retrieved June 13, 2009 (pdf).
- Louis Boisgibault, Fahad Al Kabbani (2020): Energy Transition in Metropolises, Rural Areas and Deserts. Wiley - ISTE. (Energy series) ISBN 9781786304995.
- "metropolis, n." OED Online, Oxford University Press, June 2017, www.oed.com/view/Entry/117704. Retrieved December 19, 2017; "polis, n.2." OED Online, Oxford University Press, June 2017, www.oed.com/view/Entry/146859. Retrieved December 19, 2017.
- "City Population Reporting on Instituto Nacional de Estatística, República de Angola (web) Projection July 2019". Retrieved February 12, 2018.
- Institut National De La Statistique L’Institut national de la statistique et des études économiques. "Projections demographiques 2019–25 (in French)". Retrieved September 23, 2020.
- Harrington, Rebecca. "These will be the world's 10 biggest cities in 2050 — and you probably haven't heard of some of them". Business Insider. Business Insider. Retrieved February 18, 2016.
- "2011 National Statistics". Csa.gov.et. Archived from the original on March 30, 2013. Retrieved July 20, 2013.
- "Environmental and Structural Inequalities in Greater Accra". The Journal of the International Institute. Archived from the original on October 19, 2012. Retrieved July 22, 2010.
- "Abidjan, Ivory Coast Population".
- "2019 Kenya Population and Housing Census Volume I: Population by County and Sub-County". knbs.or.ke. Retrieved November 7, 2019.
- "Population". Lagos State Government. 2011. Archived from the original on October 18, 2015. Retrieved November 3, 2012.
- Pacetti, M.; Passerini, G.; Brebbia, C.A.; Latini, G. (2012). The Sustainable City VII: Urban Regeneration and Sustainability. ISBN 9781845645786.
- "City Mayors: World's fastest growing urban areas (1)". Retrieved May 25, 2015.
- Hoornweg, Daniel; Pope, Kevin. "Socioeconomic Pathways and Regional Distribution of the World's 101 Largest Cities" (PDF). media.wix.com.
- https://www.ubos.org/wp-content/uploads/publication/09_2019Final_2020_21_LLG_IPFs_Sept_2019.pdf[ permanent dead link]
- "City Mayors: World's fastest-growing urban areas (1)". www.citymayors.com.
- Szoldra, Paul. "Unbelievable Photos Show Kabul's Dramatic Transformation From Battlefield To Modern Metropolis". Business Insider.
- "South Asia – World Population Day – July 11(South Asia Urban Growth)". World Bank. Retrieved October 29, 2012.
- "Local Government in Japan" (PDF). Council of Local Authorities for International Relations. p. 41. Archived from the original (PDF) on October 25, 2007. Retrieved October 16, 2007.
- "Population Size and Growth of Major Cities" (PDF). Demographia.com.
- "6th census of Pakistan will be held in March 2016". Siasat.pk Forums.
- "March 2017 as the month of Census in Pakistan". December 16, 2016.
- "DISTRICT WISE CENSUS RESULTS CENSUS 2017" (PDF). www.pbscensus.gov.pk. Archived from the original (PDF) on August 29, 2017. Retrieved September 3, 2017.
- "Philippine Development Plan 2017–2022, Chapter 3: An overlay of economic growth, demographic trends and physical characteristics" (PDF). National Economic and Development Authority. 2017. Retrieved April 21, 2018.
- Kumarage A, Amal. "Impacts of Transportation Infrastructure and Services on Urban Poverty and Land Development in Colombo, Sri Lanka" (PDF). November 1, 2007. Global Urban Development Volume 3 Issue 1. Retrieved August 24, 2018.
- "The 10 Traits of Globally Fluent Metro Areas" (PDF). 2013. Brookings Institution. Archived from the original (PDF) on April 2, 2015. Retrieved August 24, 2018.
- "Colombo: The Heartbeat of Sri Lanka/ Metro Colombo Urban Development Project". March 21, 2013. The World Bank. Retrieved August 24, 2018.
- "Turning Sri Lanka's Urban Vision into Policy and Action" (PDF). 2012. UN Habitat, Chapter 1, Page 7. Archived from the original (PDF) on March 4, 2016. Retrieved August 24, 2018.
- 鄉鎮市區人口及按都會區統計. Taiwan Ministry of Interior. 2013.
- "高雄市政府主計處全球資訊網 – 首頁". dbaskmg.kcg.gov.tw (in Chinese). Archived from the original on May 11, 2016. Retrieved June 6, 2016.
- "United Arab Emirates: metropolitan areas". World-gazetteer.com. Archived from the original on October 1, 2007. Retrieved July 31, 2009.
- ""Prostorni plan Kantona Sarajevo za period od 2003. do 2023. godine"" (PDF). Archived from the original (PDF) on September 6, 2018.
- "Database – Eurostat". European Commission. Retrieved December 4, 2018.
- "Statistikbanken". statistikbanken.dk. Retrieved December 4, 2018.
- Brutel, Chantal (January 18, 2011). "Un maillage du territoire français" [A network of French territory] (in French). Institut national de la statistique et des études économiques.
- "Initiativkreise Europäische Metropolregion in Deutschland: IKM". Deutsche-metropolregionen.org. Retrieved October 29, 2012.
- "How Italy puts cities in charge".
- "RUSSIA: Central'nyj Federal'nyj Okrug – Central Federal District". City Population.de. August 8, 2020. Retrieved September 1, 2020.
- "Demographia World Urban Areas" (PDF). Demographia. Retrieved July 22, 2020.
- Alexander Akishin (August 17, 2017). "A 3-Hour Commute: A Close Look At Moscow The Megapolis". Strelka Mag. Retrieved May 23, 2020.
- "Moscow, a City Undergoing Transformation". Planète Énergies. September 11, 2017. Retrieved May 27, 2020.
- "RUSSIA: Severo-Zapadnyj Federal'nyj Okrug: Northwestern Federal District". City Population.de. August 8, 2020. Retrieved October 24, 2020.
- "census metropolitan area (cma) and census agglomeration (ca), 2001 census". 2.statcan.ca. Retrieved October 29, 2012.
- "1217.0.55.001 – Glossary of Statistical Geography Terminology, 2003". Australian Bureau of Statistics.
- Statistics, c=AU; o=Commonwealth of Australia; ou=Australian Bureau of. "Media Release – Ten years of growth: Australia's population hotspots (Media Release)". abs.gov.au. Archived from the original on September 30, 2017. Retrieved January 20, 2018.
- "Censo 2010. Resultados provisionales: cuadros y gráficos" (in Spanish). Archived from the original on December 20, 2010. Retrieved February 25, 2011.
- "About Buenos Aires". EnjoyBA. Retrieved August 17, 2015.
|Wikisource has the text of the 1911 Encyclopædia Britannica article " Metropolis".|
- Census.gov, U.S. Census Bureau, About Metropolitan and Micropolitan Statistics
- MetroForum.com, forum dedicated to discussions on metropolis
- Blog.ar2com.de, a podcast with a worldwide analysis of megacities (focus Latin America)
- E-geopolis.eu at the Library of Congress Web Archives (archived October 27, 2009): research group, university of Paris-Diderot, France
- See Ronald Daus´s bibliography, researcher at the Free University of Berlin