From Wikipedia, the free encyclopedia

A megalopolis, or megapolis, is defined as an extensive metropolitan area or a long chain of roughly continuous metropolitan areas in the United States and Canada. The term was first used in the United States by Jean Gottmann in 1957, to describe the huge urban area along the Eastern seaboard of the U.S. from Boston, Massachusetts to Washington, D.C. According to Gottmann, it resulted from changes in work and social habits. See also: BosWash, ChiPitts, Quebec City-Windsor Corridor, SanSan, and Bajalta California. A megalopolis is also frequently a megacity, megapolitan area, or a metropolitan area with a total population in excess of 10 million people.

Megalopolis is used in urban studies as a term to link the metropolitan Combined Statistical Areas of Boston-Worcester-Manchester, MA-RI-NH; Hartford-West Hartford-Willimantic, CT; New York-Newark-Bridgeport, NY-NJ-CT-PA; Philadelphia-Camden-Vineland, PA-NJ-DE-MD; and Washington-Baltimore-Northern Virginia, DC-MD-VA-WV.

The Pittsburgh–Chicago Corridor is an Urban Studies term that describes the area running through the Rust Belt from the Mid-Atlantic States to the Western Great Lakes region, although great spans of agricultural land and woodlots separates the urban areas. Within this megalopolis, the Steel City Corridor ideally describes the area connecting Cleveland to Pittsburgh via Youngstown and Warren, Ohio, and Sharon–Farrell–New Castle, Pennsylvania. Historically, these areas are known as the Steel Valleys (along the Mahoning and Shenango rivers).

Modern interlinked ground transportation corridors, such as rail and highway, often aid in the development of megalopolises.

Although US based demographers did not look beyond the US and Canada, there exists roughly the same concept and structures worldwide, namely "long chains of roughly continuous metropolitan areas". Some of these terms already exist conceptually in their respective nations, albeit not using (nor aware of) the US term "megalopolis". The following is a list of dense, built up areas of multiple large cities each with suburbs that coalesce into one large urban zone or corridor, with few or little rural areas in between. Like US megalopolises, they often have a strong interlinked ground transportation backbone (rail, highway, etc) aiding in their growth. Night sky views of nations often show lit up these areas making them very obvious compared to their surroundings. They can be thought of as a worldwide (non-US centric) extension of the term "megalopolis".

This list is merely as a list of continually built up areas. Population estimates are a general guide, but the criteria are not meant for comparison. A lot of variance applies when comparing chains of metropolitan areas, as there can be several metropolitan areas definitions even for the same city, and methods differ from city to city, nation to nation, and year to year. Comparison without understanding underlying methods is meaningless.

• Taiheiyō Belt in Japan (roughly 82.9 million); dense with no rural areas at all in between.
• Beijing–Tianjin–Tangshan in China (23 million, all other Hebei cities excluded)
• Jakarta–Depok-Bogor–Tangerang–Bekasi (Jabotabek)–Bandung in Indonesia (28 million)
• West coast of Taiwan, from Taipei to Kaohsiung (18 million)
• Rhine-Ruhr in the western part of Germany (approx. 12 million incl. Cologne, Duesseldorf, Dortmund)
• Most of South Korea (Incheon–Seoul–Daejon–Daegu–Busan) (32 million)
• Mexico City-Toluca-Puebla-Cuernavaca-Pachuca-Tulancingo- Mexico (27 million)
• Delhi–New Delhi, India (18 million)
• Cairo-Giza-Kalyoubia (Greater Cairo), Egypt (16 million)
• Los Angeles--Riverside--San Bernardino--Orange--Ventura--San Diego--Santa Barbara--Imperial counties-Tijuana, Mexicali and Ensenada, Mexico, collectively known as Southern California (24 million; 21 million in S. Cal; 3+ million in Baja California, Mexico)
• San Francisco- Oakland- San Jose- Monterey- Salinas- Santa Rosa- Napa Valley- Sacramento- Stockton- Modesto- Fresno, California known as the Bay Area (San Francisco and Monterey) and outlying areas in Northern California; (11 million)
• Kolkata–Asansol, India (20 million)
• Mumbai–Pune, India (25 million)
• Lagos–Ibadan–Cotonou, including Porto Novo and Abeokuta, Nigeria (22 million)
• Boston–Providence–Hartford–New York City–Newark–Philadelphia–Wilmington–Baltimore–Washington D.C.-Richmond, known as BosWash or the Northeast Corridor, the most populous and largely developed area in the Western Hemisphere (45 million)
• Extended Golden Horseshoe - London-Tillsonburg-Ingersoll-Woodstock-Kitchener/Waterloo-Guelph-Brantford-Hamilton-Greater Toronto Area-Oshawa/Whitby-Barrie-Peterborough-Cobourg-Niagara Falls, ON/NY-Buffalo (11 million, <9 million in ON, >2 million in NY)
• Quebec City-Windsor Corridor (17 million - Canadian population only; >25 million if US border cities within 100km included)
• The Gauteng City Region (PWV), which includes the urbanised portion of Gauteng Province (Johannesburg, Pretoria and the Vaal Triangle, with a population of over 10 million), and urban areas outside the province which are functionally linked, such as Witbank-Middelburg, Secunda, Rustenburg, and Potchefstroom-Klerksdorp, pushing the population up to between 15 and 20 million ^{[1] [2] [3]}
• Buenos Aires Metropolitan area ("Gran Buenos Aires") in Argentina with 14 millon people, which includes the cities of Avellaneda, Lanús, Quilmes, Banfield, Ramos Mejía, Laferrere, Merlo, Morón, Moreno, San Miguel, San Martín, Vicente López, San Isidro, Tigre, San Fernando, Ciudadela, and others.
• Chicago-Milwaukee-Madison-Rockford-South Bend (13 million)
• Istanbul-Bursa-Çanakkale, Turkey with at least 17 million people. This is an example of a transcontinental megalopolis and Istanbul is a transcontinental city, since both cover land in both Asia and Europe.

Less clear or potential areas would include:

• ChiPitts - Green Bay-Milwaukee-Chicago-Indianapolis-Rockford-Madison-Grand Rapids-Detroit/Windsor-Fort Wayne-Toledo-Cleveland-Columbus-Cincinnati-Pittsburgh-Erie-Buffalo-Toronto-Hamilton, covering portions of 7 US states and southern part of Ontario province (see Rust Belt for historical name for same region, usage still exists but much less so than pre-1990 due to deindustrialization) (54 million)
• Rio de Janeiro–São Paulo–Campinas–Belo Horizonte, in Brazil, with approx 49 million inhabitants (includes the Volta Redonda, Campos dos Goytacazes, Juiz de Fora, Divinopolis areas)
• The multinational Blue Banana (Banane bleue in French, Blaue Banane in German, and Blauwe Banaan in Dutch) stretching from the conurbations of the West Midlands (region), North West England and Yorkshire and the Humber (around 6 million) and then through London (14 million) all in the United Kingdom, across the English Channel, through Paris (12 million), France, the Lille-Kortrijk-Tournai Euregion (1.8 million), France and Belgium, the Flemish Diamond (5.5 million), Belgium, the Randstad (the Brabantse Stedenrij and Knooppunt Arnhem-Nijmegen agglomerations included) (10.5 million), Netherlands, the Gronau-Enschede Euregion (3,2 million), Germany and the Netherlandsthe Meuse-Rhine Euregion (3.9 million), Belgium, Netherlands and Germany, the Rhine-Ruhr in Germany, Frankfurt Rhine Main Area (5.3 million), Germany, Basel metropolitan area (around 700.000 people), Switzerland, Zurich metropolitan area (1.3 million), Switzerland, to Milan (9 million) and Turin (2,5 million), Italy (Total around 85 million) (also called European Megalopolis).
• The Pearl River Delta (PRD) in Guangdong region, China could be considered a megalopolis, as it is dense and contains 11 cities including Hong Kong (7 million), Macau (0.5 million), Guangzhou (over 10 million), Shenzhen (over 7 million), Zhuhai (1.3 million), Dongguan (6.6 million), Foshan (5.5 million), Jiangmen (4.1 million), parts of Zhaoqing (3.4 million), parts of Huizhou (3.3 million) and Zhongshan (2.4 million). (Total 50 million, migrant workers included)
• The Yangtze River Delta between southern Jiangsu province and northern Zhejiang, China could also be considered a megalopolis, though less developed compared to the Pearl River Delta. It contains at least 16 cities including Shanghai (over 15 million), Nanjing (6.4 million), Hangzhou (6.4 million), Ningbo (5.5 million), Nantong(7.7 million), Suzhou (6.1 million), Taizhou (5.5 million), Taizhou (5.0 million), Yangzhou (4.5 million), Wuxi (4.5 million) ,Shaoxing (4.4 million), Changzhou (3.5 million), Jiaxing (3.3 million), Zhenjiang (2.7 million), Huzhou (2.6 million) and Zhoushan (1 million). (Total 80 million)
• The central Liaoning city cluster in China. Within 150km from its center Shenyang (7.2 million), it has Fushun (3 million), Anshan (3.6 million), Benxi (1.5 million), Liaoyang (1.8 million), Yingkou (2.2 million), Panjin (1.2 million), and Tieling (3.4 million), with a total population of 23 million. And it can be further extended to Dalian (6.2 million), Fuxin (2 million) and Dandong (2.4 million). This area used to be the most industrialized region in China. It declined during 1980s - 1990s, but in recent years, it rapidly revives.
• Perhaps the hardest to determine is the Ganges river valley (Indo-Gangetic Plain) from Islamabad through Lahore and Delhi to Kolkata and into Bangladesh that contains a vast swath of cities of different sizes and is approaching one billion inhabitants. It is difficult to say where a megalopolis starts and ends here.
• A potential megalopolis is that of southern Florida. This beach lovers land extends from Jupiter, West Palm Beach, and Wellington in the north, south to Miami. The Everglades form a natural boundary for this potential megalopolis in the south and west.
• The "Orlampa" megalopolis in Florida, which if Florida continues to become as densely populated as expected over the next thirty years, an H-shaped megalopolis will swallow up rural areas surrounding Orlando, Tampa, St. Petersburg, Clearwater, Sarasota, Bradenton, Lakeland, Winter Haven, Sanford, Oviedo, Daytona Beach, Cocoa Beach, and Kissimmee.
• The I-85 Corridor in the Southeastern United States: Raleigh-Durham-Greensboro-Winston-Salem-Charlotte-Spartanburg Greenville-Atlanta.
• Similarly, Atlanta and the areas connected to it via interstate, including Chattanooga to Macon via I-75, Augusta to Birmingham via I-20, and northwards from there out the aforementioned I-85 Corridor. This theoretical megalopolis would eventually cover most of the state of Georgia.
• A potential megalopolis stretches along Interstate 40 from North Carolina to Arkansas, and includes Wilmington, Raleigh, Durham, Greensboro, Winston-Salem, Asheville, Knoxville, Nashville and Memphis. This area is growing toward the I-85 Corridor by way of several counties in the northern portion of the Charlotte area, as well as Asheville's long-standing economic ties to Greenville and Spartanburg.
• Similarly, the three largest metropolitan areas in East Tennessee--Knoxville, Chattanooga, and the Tri-Cities (Johnson City, Tennessee, Kingsport, Tennessee and Bristol, Tennessee-Virginia) have long had close political and economic connections to each other. This developing cluster is connected to the I-40 cluster by way of Knoxville.
• The I-35 Corridor in Texas, Oklahoma, and Kansas beginning in San Antonio (1.9 million) and extending through Austin-Round Rock (1.5 million), Temple-Killeen (350,000), Waco (225,000), Dallas-Fort Worth (6.0 million), Oklahoma City (1.2 million), Tulsa, Oklahoma (900,000), Wichita, Kansas (600,000), and Kansas City (2.0 million)^[4].
• The Front Range centered on Denver-Boulder, Colorado, and extending north through Fort Collins and Greeley, Colorado, and Cheyenne, Wyoming, south through Colorado Springs and Pueblo.
• California's Great Central Valley: Redding- Red Bluff- Chico- Oroville- Yuba City- Marysville- Roseville- Sacramento- Woodland- Davis- Lodi- Stockton- Manteca- Modesto- Turlock- Merced- Madera- Fresno- Tulare- Visalia- Hanford- Bakersfield; This area stretches about 500 miles through the central section of the US state of California- It also includes some outlying East Bay, California Delta / Sacramento- San Joaquin River Delta and Pacific Coast Range foothill communities to the west as well as some Cascade Mountain Range and Sierra Nevada foothill communities to the east. It's northern boundary is Redding in Shasta County, just south of Shasta Lake and Mt. Shasta in the Cascade Mountain Range (although some will say that Red Bluff is actually the northern boundary) and it's southern boundary is the northern base of the Tehachapi Mountains (also known as "The Grapevine)" in Kern County north of Los Angeles- Divided into two sections, The Sacramento Valley comprises that extending north from the Sacramento- San Joaquin River Delta and the San Joaquin Valley is that area extending south of the Sacramento- San Joaquin River Delta- Interstate 80 and many state highways cross the valley in an east- west direction; Heavily traveled Interstate 5 serves as the main artery between the San Francsco Bay Area and Los Angeles as it is a shorter route than the much more scenic US 101 which runs along the Pacific Coast. Historic California Highway 99 (fomerly US Highway 99, the other primary north- south route, intersects Interstate 5 in Red Bluff and runs parallel all the way to the base of The Grapevine where it rejoins Interstate 5 leading into Los Angeles and San Diego; Several other state highways also run north- south (7 million)
• The Cascade megalopolis, which includes Vancouver, British Columbia, Seattle-Bellingham-Everett, Washington, Tacoma, Olympia, Portland, Oregon-Vancouver, Washington, Salem, Oregon, Albany-Corvallis, and Eugene-Springfield.
• NSW - Newcastle (512,000) Sydney (4.3 million) Wollongong (280,000) and Canberra (330,000) - little separates these three cities and many have speculated that they will eventually form a megalopolis
• The Northstar Corridor, which includes the Minneapolis-Saint Paul metro area and the communities along I-94 and U.S. Route 10 between the St. Cloud metro area and Minneapolis-Saint Paul, including Elk River, Monticello, Big Lake Clearwater, Clear Lake and the St. Cloud area. The corridor has a population of approximately 3.6 million and is one of the fastest-growing areas in the United States.
• Southeast Queensland - Brisbane (over 1.9 million), the Gold and Sunshine coasts, (0.7 million and 0.3 million), as well as the cities of Ipswich (150k), Redcliffe (60k), Logan (180k), Caloundra (100k) and several urban shires. The urban area is growing to the point where it has almost attached the city of Toowoomba, Queensland (135k). By 2030 the population of this megapolis could rech 6 million.

• Amalgamation (politics)
• Arcology
• Conurbation
• Ecumenopolis
• Ekistics
• Global city
• List of megalopoleis
• Megacity
• Megapolitan Area
• Metroplex
• Metropolis
• Metropolitan area
• Urban agglomeration