Twin cities

300px|thumb|High-rise buildings in Minneapolis's [[Cedar-Riverside, Minneapolis|Cedar-Riverside neighborhood, with the Downtown Saint Paul skyline visible in the background ten miles away. Minneapolis' city limits border those of Saint Paul, the capital of Minnesota. This gave birth to the nickname of the region, the "Twin Cities" metropolitan area.]]

thumb|300px|A view of the town of [[Tornio (Finland), which forms a twin city with Haparanda (Sweden)]]

Twin cities are two neighboring cities or urban areas that are generally comparable in status and size, though not necessarily equal. Although there are no formal criteria, a city and a substantially smaller suburb would not typically qualify, even if they were once separate. Tri-cities and quad cities are similar groups of three or four municipalities, respectively.

A common but not universal scenario is two cities that developed concurrently on opposite sides of a river. For example, Minneapolis and Saint Paul in Minnesota—one of the most widely known pairs of "Twin Cities"—were founded several miles apart on opposite sides of the Mississippi River, and competed for prominence as they grew.

In some cases, twin cities are separated by a state border, such as Albury (New South Wales) and Wodonga (Victoria) in Australia, on opposite sides of the Murray River. In Pakistan, Islamabad and Rawalpindi are twin cities located in the northwestern Punjab region; Islamabad is administratively part of the Islamabad Capital Territory, and Rawalpindi is in the province of Punjab. Cities on opposite sides of international borders sometimes share enough cultural and historical identity to be seen as twins, such as Haparanda (Sweden) and Tornio (Finland), Leticia (Colombia) and Tabatinga (Brazil), or Valga (Estonia) and Valka (Latvia).

In some cases, twin cities eventually merge into a single legal municipality, such as Buda and Pest merging in 1873 into Budapest, Hungary; Brooklyn and New York City being consolidated in 1898; and the three ancient cities of Hankou, Hanyang, and Wuchang joining in 1927 into Wuhan. As a single urban area, twin cities may share an airport whose airport codes include both cities' initials, e.g. DFW (Dallas–Fort Worth), LBA (Leeds–Bradford), MSP (Minneapolis–Saint Paul), RDU (Raleigh and Durham), and CAK (Akron–Canton).

thumb|right|Cross-border example of twin cities: Plaza Internacional of the [[Frontera de la Paz. On the left, Santana do Livramento (Brazil); on the right, Rivera (Uruguay).]]

List of international and regional border towns and cities

Africa

{| class="wikitable"

! Border towns!! Countries

|Kinshasa and Brazzaville

| /

|Goma and Gisenyi

| /

|Kousséri and N'Djamena

| /

|Aflao and Lomé

| /

| Victoria Falls and Livingstone

| /

Asia

{| class="wikitable"

! Border towns

! Countries

|Astara and Astara

| /

|Erenhot and Zamyn-Üüd

| /

|Dandong and Sinuiju

| rowspan="3" | /

|Changbai and Hyesan

|Ji'an and Manpo

|Manzhouli and Zabaykalsk

| rowspan="2" | /

|Heihe and Blagoveshchensk

|Dongxing and Mong Cai

| rowspan="2" | /

|Hekou and Lao Cai

|Johor Bahru and Singapore

| /

|Vientiane and Nong Khai

| /

|Dansavan and Lao Bao

| /

|Al Ain and Al Buraimi

| /

|Agartala and Akhaura

| /

|Eilat and Aqaba

| /

|Jincheng and Xiamen

| /

|Hong Kong and Shenzhen

| /

Europe

{| class="wikitable"

! Border towns!! Countries

|Vienna and Bratislava || /

|Bad Radkersburg and Gornja Radgona || /

|Comines and Comines || rowspan="3" | /

|Mouscron and Tourcoing

|Wervik and Wervicq-Sud

|Slavonski Brod and Bosanski Brod || /

|Český Těšín and Cieszyn || /

|Copenhagen and Malmö || rowspan="2" | /

|Helsingør and Helsingborg

|Valga and Valka || /

|Narva and Ivangorod

| /

|Imatra and Svetogorsk || /

|Tornio and Haparanda || /

|Strasbourg and Kehl || /

|Hendaye and Irun || /

|Frankfurt (Oder) and Słubice || rowspan="4" | /

|Görlitz and Zgorzelec

|Guben and Gubin

|Heringsdorf and Świnoujście

|Konstanz and Kreuzlingen || rowspan="2" | /

|Laufenburg (Baden) and Laufenburg, Aargau

|Esztergom and Štúrovo || rowspan="2" | /

|Komárno and Komárom

|Strabane and Lifford || /

|Gorizia and Nova Gorica || /

|Kerkrade and Herzogenrath || /

|La Línea de la Concepción and Gibraltar || /

|Basel, Weil am Rhein and Saint Louis || / /

|Sarp and Sarpi || / }

|Tui and Valença

| /

|Aubange, Longwy and Pétange

| / /

;Notes

North America

{| class="wikitable sortable"

! Border towns!! Bordering countries

| Niagara Falls, Ontario and Niagara Falls, New York|| rowspan="4" | /

| Sault Ste. Marie, Ontario and Sault Ste. Marie, Michigan

| Stanstead, Quebec and Derby Line, Vermont

| North Portal, Saskatchewan and Portal, North Dakota

|Tecate, Baja California and Tecate, California|| rowspan="8" | /

| Boquillas del Carmen, Coahuila and Boquillas, Texas

| Naco, Sonora and Naco, Arizona

| Nogales, Sonora and Nogales, Arizona

| San Luis Río Colorado, Sonora and San Luis, Arizona

| Nuevo Laredo, Tamaulipas and Laredo, Texas

| Nuevo Progreso, Río Bravo, Tamaulipas and Progreso, Texas

| Calexico, California and Mexicali, Baja California (Calexico–Mexicali)

| Ciudad Hidalgo, Chiapas and Ayutla, San Marcos

| /

| Detroit, Michigan and Windsor, Ontario (Detroit–Windsor)

| rowspan="2" | /

| International Falls, Minnesota and Fort Frances, Ontario

| Douglas, Arizona and Agua Prieta, Sonora

| rowspan="8" | /

| Yuma, Arizona and San Luis Río Colorado, Sonora

| San Diego, California and Tijuana, Baja California see San Diego–Tijuana

| Brownsville, Texas and Matamoros, Tamaulipas see Brownsville–Matamoros

| Del Rio, Texas and Ciudad Acuña, Coahuila

| Eagle Pass, Texas and Piedras Negras, Coahuila

| El Paso, Texas and Ciudad Juárez, Chihuahua see El Paso–Juárez

| Presidio, Texas and Manuel Ojinaga, Chihuahua

South America

{| class="wikitable sortable"

! Border town!! Countries

|Sant'Ana do Livramento and Rivera

| /

|Chuí and Chuy

| /

|Puerto Iguazú, Foz do Iguaçu, Ciudad del Este, and Presidente Franco

| / /

|Posadas and Encarnación

| /

|Concordia and Salto

| /

|Salvador Mazza and Yacuiba

| /

List of internal border towns and cities

Africa

{| class="wikitable"

! Twin towns!! Country

| Cairo and Giza. Triple cities if counting Shubra El Kheima.

| rowspan="2" |

|Port Said and Port Fuad

| Sekondi-Takoradi

|Asaba and Onitsha

| rowspan="2" |

|Jimeta and Yola

| Johannesburg and Pretoria, Gauteng Province

Asia

{| class="wikitable"

! Twin towns!! Country

|Dhaka and Narayanganj

|Guangzhou and Foshan

| rowspan="6" |

|Xi'an and Xianyang

|Beijing and Langfang

|Wuxi and Suzhou

|Chaozhou and Shantou

|Haifeng and Lufeng

|Ahmedabad and Gandhinagar, Gujarat

| rowspan="41" |

|Allahabad and Naini, Uttar Pradesh

|Durg and Bhilai, Chhattisgarh

|Kolkata and Howrah, West Bengal

| Wuhan (merger of Wuchang, Hankou, Hanyang)

| Chirala-Perala

| rowspan="2" |

|Bangalore Cantonment and Bengaluru Pete along with their suburbs merged to form modern Bangalore

| Fukuoka (merger of east side of Naka river, Hakata, and the west side, Fukuoka)

| rowspan="4" |

| Ise (merger of Uji, Yamada)

| Joetsu (merger of Takada, Naoetsu)

| Naha and Shuri, Okinawa, once separate cities. Shuri became integrated as a district of Naha.

| Iloilo and Jaro, once separate cities, were consolidated into Iloilo City.

| Zhongli and Taoyuan, merged into Taoyuan City.

| Saigon and Cholon, merged into Saigon-Cholon, now Ho Chi Minh City.

Europe

{| class="wikitable"

! Twin towns!! Country

| Nørresundby and Aalborg

|Kotka and Hamina

| Frejus and Saint-Raphaël

| rowspan="2" |

| Lyon and Villeurbanne

|Göteborg and Mölndal

| Düsseldorf and Neuss

| rowspan="9" |

| Frankfurt and Offenbach

| Ludwigshafen and Mannheim

| Mainz and Wiesbaden

| Mönchengladbach and Rheydt

| Nuremberg and Fuerth

| Sindelfingen and Böblingen

| Ulm and Neu-Ulm

| Villingen-Schwenningen

|Ballybofey and Stranorlar, in County Donegal, Ireland are often called the Twin Towns and form the built up area of Ballybofey and Stranorlar

|Fredrikstad and Sarpsborg

| rowspan="3" |

| Porsgrunn and Skien. Together with Tollnes, Gulset and Åfoss they form the Grenland urban area.

| Sandnes and Stavanger

|Bydgoszcz and Toruń

| rowspan="2" |

| Kalisz and Ostrów Wielkopolski

|Porto and Vila Nova de Gaia

| rowspan="2" |

| Póvoa de Varzim and Vila do Conde

|Alcobendas and San Sebastián de los Reyes

| rowspan="7" |

| Aldaia and Alaquàs

| Coslada and San Fernando de Henares

| Elda and Petrer

| Llombai and Catadau

| Santa Cruz de Tenerife and San Cristóbal de la Laguna

| Ferrol and Narón

|Jönköping and Huskvarna

|Donetsk and Makiivka

| rowspan="4" |

|Kramatorsk and Sloviansk

|Sievierodonetsk and Lysychansk

|Pokrovsk and Myrnohrad

| Brighton and Hove

| rowspan="7" |

| Chatham and Rochester

| Leeds and Bradford

| Manchester and Salford

| Newcastle upon Tyne and Gateshead

| Liverpool and Birkenhead

| Warwick and Leamington Spa

Historic

{| class="wikitable"

! Twin towns!! Country

|Knokke and Heist-aan-Zee. United into Knokke-Heist||

|Frýdek and Místek. United into Frýdek-Místek||

|Barmen and Elberfeld. United into Wuppertal.|| rowspan="2" |

|Bonn and Beuel. United into Bonn.

|Kouvola and Kuusankoski. United into Kouvola.|| rowspan="2" |

|Äänekoski and Suolahti. United into Äänekoski.

|West Berlin, West Germany and East Berlin. United into Berlin.||

|Buda and Pest. United into Budapest.

| rowspan="5" |

|Vijayawada; Amaravati; and Guntur

|Chennai, Avadi and Tambaram

|Ranipet, Walajapet and Arcot

|Warangal; Hanamkonda; Kazipet — see Warangal Tri-City

|Kyoto; Osaka; Kobe - see Keihanshin

|Parit Buntar, Perak; Nibong Tebal, Penang; and Bandar Baharu, Kedah

|Guadalajara; Tlaquepaque; Zapopan, Jalisco

|Bhaktapur; Kathmandu; and Patan

| rowspan="2" |

|Tricity, consisting of the cities of Baglung, Beni and Kushma

|Bacolod; Silay; Talisay

| rowspan="3" |

|Cebu City; Mandaue; and Lapu-Lapu City

|Angeles City; Mabalacat; and San Fernando

|Gdańsk; Gdynia; and Sopot — see Tricity

| rowspan="2" |

|Wejherowo; Rumia; and Reda — see Kashubian Tricity

|The Dammam metropolitan area, consisting of Dammam; Dhahran; and Khobar

|The metropolitan municipalities of Johannesburg, Tshwane (Pretoria) and Ekurhuleni (East Rand), Gauteng Province

| rowspan="3" |

|Gqeberha (Port Elizabeth), Kariega (Uitenhage) and Despatch in Nelson Mandela Bay Metropolitan Municipality, Eastern Cape Province

|East London, Bhisho and Qonce (King William's Town) in Buffalo City Metropolitan Municipality, Eastern Cape Province

|Khartoum; North Khartoum; and Omdurman

|Stockholm; Solna; and Sundbyberg

| rowspan="2" |

|Trollhättan; Uddevalla; and Vänersborg

|The Dubai-Sharjah-Ajman metropolitan area, consisting of Dubai; Sharjah; and Ajman, United Arab Emirates

|Burbank; Glendale; and Pasadena, in Los Angeles County, California

| rowspan="25" |

|Fremont; Newark; and Union City, in Alameda County, California

|Oceanside; Vista; and Carlsbad, in San Diego County, California

|Riverside; San Bernardino; and Ontario, California, the cities' collective metropolitan area is often called the Inland Empire

|San Jose; San Francisco; and Oakland, California

|College Park; East Point; and Hapeville, Georgia, all of which are near Hartsfield–Jackson Atlanta International Airport

|Bay City; Saginaw; and Midland, Michigan, the cities' collective metropolitan area is often called the Greater Tri Cities, the Great Lakes Bay Region or the MBS region

|Ferrysburg; Grand Haven; and Spring Lake, Michigan

|Iron River, Caspian, and Gaastra, Michigan

|Ironwood; Bessemer; and Wakefield, Michigan

|Grand Island; Kearney; and Hastings, in south-central Nebraska, also known as Tri-Cities, Nebraska

|Rochester; Dover; and Somersworth, New Hampshire

|Farmington; Bloomfield; and Aztec, New Mexico

|Albany, Troy, and Schenectady, New York, in the region known as the Capital District

|Binghamton; Endicott; and Johnson City, New York, the cities' collective metropolitan area is often called the Triple Cities

|New York, New York; Newark; and Jersey City, New Jersey

|Greensboro; Winston-Salem; and High Point, North Carolina, the cities' collective metropolitan area is often called the Piedmont Triad

|Raleigh; Durham; and Chapel Hill, North Carolina, the cities' collective metropolitan area is often called the Research Triangle

|Tuttle; Newcastle; and Blanchard, Oklahoma, also known as the Tri-City Area

|Johnson City; Kingsport; and Bristol, Tennessee/Bristol, Virginia, also known as Tri-Cities, Tennessee

|Beaumont; Port Arthur; and Orange, Texas, also known as the Golden Triangle (Texas)

|Dallas; Fort Worth; and Arlington, Texas

|Petersburg; Colonial Heights; and Hopewell, Virginia, also known as Tri-Cities, Virginia

|Pasco; Richland; and Kennewick, Washington, also known as Tri-Cities, Washington

|Washington, D.C., Alexandria, Virginia, and Arlington County, Virginia

Quad cities

{| class="wikitable sortable"

! Border towns!! Bordering countries

|Xinhui, Taishan, Kaiping, and Enping together formed Siyi area in Jiangmen, Guangdong

|Helsinki, Espoo, Kauniainen and Vantaa in Uusimaa; together form the largest metropolis in the country and its actual capital area.

|Pattaya–Chonburi metropolitan area, consisting of the City of Pattaya, Town of Chonburi, Portal town of Laem Chabang and Town of Sattahip on the west coast of Chonburi Province, Thailand

|The West Yorkshire Built-up Area consists of the cities of Leeds, Bradford and Wakefield, and the large town of Huddersfield, United Kingdom.

|The Florence-Muscle Shoals Metropolitan Area in Alabama, is locally referred to as "the Quad Cities", with Florence, Muscle Shoals, Sheffield, and Tuscumbia, Alabama. Formerly, when Muscle Shoals was a mere village, this region was known as "Tri-Cities", Alabama. In fact, all except Florence are incorporated as towns.

| rowspan="5" |

|Quad Cities of Davenport and Bettendorf, Iowa, and Rock Island and Moline, Illinois. It also includes a fifth member, East Moline, Illinois.

|Allentown/Bethlehem, Pennsylvania and Easton, Pennsylvania/Phillipsburg, New Jersey; the collective area is often called the Lehigh Valley

|The Quad Cities of Minnesota, consist of Virginia, Eveleth, Gilbert, and Mountain Iron.

|The cities of Pullman, Washington, Moscow, Idaho, Lewiston, Idaho and Clarkston, Washington, have marketed themselves as "Quad Cities."

More than four cities

{| class="wikitable sortable"

! Border towns!! Country

|The Triangle Region, consisting of Billund, Fredericia, Haderslev, Kolding, Middelfart, Vejen and Vejle.

|The Ruhr district consisting of Dortmund, Essen, Duisburg, Bochum, Oberhausen, Mülheim, Bottrop, Gelsenkirchen and Herne in its core.

|The cities of New Delhi, Noida, Greater Noida, Ghaziabad, Gurgaon and Faridabad have formed a huge metropolitan area known as National Capital Region (India).

|rowspan="2"|

|The cities of Mumbai, Thane, Navi Mumbai, Kalyan-Dombivli, Mira-Bhayandar, Vasai-Virar, Panvel, Bhiwandi, Ulhasnagar, Ambarnath and Badlapur have formed a huge Mumbai Metropolitan Region.

|The cities of Kuala Lumpur, Petaling Jaya, Subang Jaya, Puchong, Shah Alam, Klang, Port Klang, Putrajaya, Cyberjaya and Kajang have formed a huge metropolitan area (around the size of Singapore) known as Greater Kuala Lumpur.

|The cities of Karaganda, Temirtau, Shakhtinsk, Abai, Saran, Topar, Dolinka, Shahan, Kokpekti, and Novodolinsky form an industrial-mining area known since Soviet times as Karbass (Karaganda coal basin).

|The cities of Będzin, Bytom, Chorzów, Czeladź, Dąbrowa Górnicza, Gliwice, Jaworzno, Katowice, Knurów, Mikołów, Mysłowice, Piekary Śląskie, Ruda Śląska, Siemianowice Śląskie, Świętochłowice, Sosnowiec, Tychy, Tarnowskie Góry, and Zabrze form the Katowice urban area.

|Illinois and Iowa: The cities of Davenport and Bettendorf in Iowa; Rock Island, Moline and East Moline in Illinois form a metropolitan area known as the Quad Cities.

| rowspan="3" |

|Michigan and Wisconsin include the 6 cities of Iron Mountain, Kingsford, Quinnesec (in Michigan), Aurora, and Niagara (in Wisconsin). The area is collectively known as the Iron Mountain Area.

|Virginia: Norfolk, Chesapeake, Hampton, Newport News, Portsmouth, Suffolk, and Virginia Beach; the cities' collective metropolitan area is often called Hampton Roads

Unincorporated communities

Even unincorporated communities, which are called "cities" in everyday conversation, can also be called "twin cities" if they also have a neighbor that's also unincorporated, or even a proper city.

Examples:

Dorr, Michigan and Moline, Michigan
Hessel, Michigan and Cedarville, Michigan
Kinross, Michigan and Kincheloe, Michigan
Prudenville, Michigan and Houghton Lake, Michigan
Haslett, Michigan and Okemos, Michigan

Examples of cities formed by amalgamation

Asia

:China

:* Wuhan in China consists of the towns of Wuchang, Hankou, and Hanyang in Hubei Province.

:India

:* Delhi: What used to be Old Delhi, New Delhi, and a collection of smaller villages has now grown into the current megalopolis that is seen today, also known as the National Capital Region (NCR)

:* In Telangana, the cities of Hyderabad and Secunderabad are merged to form Greater Hyderabad.

:Japan

:* Fukuoka in Japan, a city of 1.4 million people, formerly the twin cities of Hakata and Fukuoka until the late 19th century.

:* Kitakyushu in Japan, a city of 900,000 people, created in 1963 by the merger of Yahata, Kokura, Moji, Wakamatsu, and Tobata. Yahata and Kokura had formerly been major cities in their own right.

:* Saitama in Japan, a city of 1.2 million people, created in 2001 by the merger of the cities of Urawa, Omiya, Yono, and later Iwatsuki. Urawa and Omiya could formerly have been considered twin cities.

:Pakistan

:* Islamabad, the capital city of Pakistan, has been expanded to include smaller towns including Rawat in its territory.

:* Lahore, the second largest city of Pakistan, has, as of 2013, grown out so much that small towns by this giant city, such as Shahdara, have been absorbed in its city limits.

:Philippines

:* Manila, the capital city of the Philippines, was reorganized in 1901 by merging several municipalities, including Tondo, Sampaloc, Paco, Pandacan, Ermita, and Malate, into one city when its borders were extended outside the walled city now known as Intramuros.

:* Iloilo City, in the Visayas, was expanded to absorb the municipalities of Molo, La Paz, Arevalo, and Mandurriao in 1937 as districts. The nearby city of Jaro was later absorbed in 1941.

:Taiwan

:* The former cities of Taoyuan and Zhongli, Taiwan, which merged along with the entire county in 2014 to form a single municipality city of Taoyuan, the two cities sit directly next to each other and shares almost the same population.

:Thailand

:* Bangkok, the capital and largest city of Thailand, was created in 1971, when the previous Bangkok province (Phra Nakhon) was merged with Thonburi province.

:Vietnam

:* The cities of Saigon and Cholon merged in 1931 to form a single city named Saigon-Cholon; in 1956, the name Cholon was dropped and the city became known as Saigon (now Ho Chi Minh City).

:* The city of Hà Đông, capital of Hà Tây Province was merged into Hà Nội upon the latter's amalgamation into Hà Nội in August 2008. Since then, Hà Đông became an urban district (quận) of Hà Nội.

Europe

:Germany

:* Berlin (Berlin and Cölln), in Germany

:* Duisburg (Duisburg and Hamborn, 1929–1935 called Duisburg-Hamborn), in North Rhine-Westphalia

:* Krefeld (Krefeld and Uerdingen, 1929–1940 called Krefeld-Uerdingen), in North Rhine-Westphalia

:* Wuppertal (Barmen and Elberfeld), in North Rhine-Westphalia

:Greece

:* Athens incorporated dozens of villages and towns and absorbed whole of Athens basin and parts outside of it, notably Piraeus.

:Hungary

:* Budapest, Hungary is the amalgamation of Buda, Pest and Óbuda.

:United Kingdom

:* Edinburgh, Scotland, absorbed a number of surrounding villages, but most notably the separate burgh of Leith.

:* London, grew from its cores in the City of London and the City of Westminster to encompass many other towns and villages within neighbouring counties and absorbed almost the whole of Middlesex county.

:* Manchester and the city of Salford in the Metropolitan County of Greater Manchester (formerly in Lancashire).

:* Stoke-on-Trent was created in 1910 from the towns of Burslem, Hanley, Tunstall, Longton, Fenton and Stoke, taking its name from the latter. Neighbouring Newcastle-under-Lyme remains a separate town.

North America

:Canada

:* Port Alberni, British Columbia, Canada, was formed in 1967 when Alberni and Port Alberni, merged to become one city.

:* Winnipeg, Manitoba, Canada, amalgamated with 12 surrounding municipalities and its metropolitan corporation in 1971 under what was referred to as unicity reforms in local government restructuring.

:* Halifax and Dartmouth, Nova Scotia, Canada, were merged in 1996 along with Bedford and Halifax County to create the Halifax Regional Municipality.

:* Greater Sudbury, Ontario, Canada, was formed in 2001 by the amalgamation of the former Regional Municipality of Sudbury, comprising the municipalities of Sudbury, Nickel Centre, Valley East, Capreol, Rayside-Balfour, Onaping Falls and Walden, plus a number of previously unamalgamated townships. The amalgamation made it the most populous city in the Northern Ontario region.

:* Kingston, Ontario, Canada, was amalgamated in 1998 with the neighboring Kingston and Pittsburgh Townships.

:* Ottawa, Ontario, Canada, was given its large area by the amalgamation in 2001 of the old City of Ottawa, the suburbs of Nepean, Kanata, Gloucester, Rockcliffe Park, Vanier and Cumberland, Orleans, and the rural townships of West Carleton, Osgoode, Rideau, and Goulbourn

:* Toronto, Ontario, Canada, formed by an amalgamation of the Old Toronto with East York, Etobicoke, North York, Scarborough and York, which were themselves products of earlier amalgamations.

:* Thunder Bay, Ontario, Canada (Fort William and Port Arthur).

:* Gatineau, Quebec, Canada, formed by the amalgamation of the old City of Gatineau, City of Hull, City of Aylmer, City of Buckingham and the Municipality of Masson-Angers all facing the City of Ottawa, Ontario from the north shore of the Ottawa River.

:* Montreal, Quebec, Canada, was merged with the other 27 communities on the Island of Montreal by an act in the Quebec Parliament in 2002. Following a change in the provincial government, several communities later voted via referendum to de-merge and there are now a total of 15, leaving Montreal merged with the other 12.

:* Saguenay, Quebec, Canada (Chicoutimi, Jonquière, et al.)

:* Lloydminster, Canada, on the Saskatchewan-Alberta border, was formed as a single entity in 1903, when both future provinces were part of the Northwest Territories, but was divided into two separate entities in 1905 because the border between the newly created provinces bisected the community. In 1930, the two towns were reunited as a single town under the shared jurisdiction of both provinces, and Lloydminster was reincorporated as a single city in 1958.

:United States

:* Helena–West Helena, Arkansas was formed in 2006 by the merger of the previous cities of Helena and West Helena.

:* Fremont, California was formed in 1956 by the combination of the five towns of Centerville, Irvington, Niles, Mission San Jose, and Warm Springs, California. The town of Newark has always refused to merge into Fremont, and Newark is completely surrounded by Fremont.

:* Cahokia Heights, Illinois was formed in 2021 when the municipalities of Alorton, Cahokia, and Centreville voted in a 2020 referendum to merge.

:* Boston, Massachusetts is made up of the former towns of Boston, Dorchester, Brighton, Roxbury, Charlestown, and Hyde Park.

:* Iron River, Michigan absorbed the nearby city of Stambaugh and village of Mineral Hills in July 2000.

:* Minneapolis, Minnesota. St. Anthony (not to be confused with St. Anthony Village, a modern city which is a suburb) was a twin city to Minneapolis in the two cities' youth. Minneapolis annexed St. Anthony in the late 1800s.

:* Park Hills, Missouri was formed in 1994 by a four-way municipal merger involving the cities of Flat River, Elvins, and Esther, plus the village of Rivermines.

:* Jersey City, New Jersey, was incorporated in 1820, and slowly grew by annexing surrounding municipalities: Van Vorst Twp. (1851), Bergen City (1869), Hudson City (1869), Bergen Twp. (1869) and finally Greenville Twp. (1873).

:* New York City, New York (five boroughs, historically especially between Manhattan and Brooklyn)

:* What is now the city of Winston-Salem, North Carolina was once two separate towns called Winston and Salem that were combined into one.

:* Cleveland (Cleveland and Ohio City) in Ohio

:* Lincoln City, Oregon was formed in 1965 by merging the extant seaside towns of Oceanlake, Delake, and Taft, with the adjoining unincorporated areas of Nelscott and Cutler City.

:* Bethlehem, Pennsylvania, which absorbed the cities of South Bethlehem, and West Bethlehem. The former Bethlehem and South Bethlehem are situated in Northampton County, and West Bethlehem is in Lehigh County. As a result, present-day Bethlehem straddles the county line.

:* Pittsburgh, Pennsylvania, annexed Allegheny City, which is now the quarter of the city that lies north of the Allegheny and Ohio rivers. Also annexed was Birmingham, now referred to as the "South Side".

:* Richmond (Richmond and Manchester) in central Virginia

:* Bellingham, Washington was formed from four cities, Fairhaven, Sehome, Bellingham and Whatcom.

Fictional twin cities

Ankh-Morpork, from Terry Pratchett's Discworld novels, is referred to as "the twin cities of proud Ankh and pestilent Morpork"
Besźel and Ul Qoma in China Miéville's novel The City & the City are intertwined twin city-states in Eastern Europe whose inhabitants have trained themselves to only see the city they live in and unsee the city they don't.
Central City and Keystone City, from the current Flash comics, are shown as twin cities. Before the 1985-86 miniseries Crisis on Infinite Earths, Central and Keystone are presented as located in the same space but on different parallel Earths.
Duckburg and St. Canard were depicted in the cartoon Darkwing Duck as sister cities connected by a bridge, very similar to Oakland and San Francisco.
Gotham City (the home of Batman) and Metropolis (the home of Superman) have sometimes been presented as twin cities, mainly in 1970s and 1980s stories by DC Comics. In stories presenting them as twin cities, Gotham City and Metropolis are located on opposite sides of a large bay (identified as Delaware Bay in 1990's The Atlas of the DC Universe), with both cities linked by the Metro–Narrows Bridge, a suspension bridge resembling New York City's Verrazzano–Narrows Bridge.
Helium, from the Barsoom series of novels by Edgar Rice Burroughs, consists of the twin cities Greater Helium and Lesser Helium.

Twin cities

Twin cities

List of international and regional border towns and cities

Africa

Asia

Europe

North America

South America

List of internal border towns and cities

Africa

Asia

Europe

Historic

Quad cities

More than four cities

Unincorporated communities

Examples of cities formed by amalgamation

Asia

Europe

North America

Fictional twin cities

See also

Notes

References