# Twin cities

Twin cities are a special case of two neighboring cities or urban centres that grow into a single conurbation – or narrowly separated urban areas – over time. There are no formal criteria, but twin cities are generally comparable in status and size, though not necessarily equal; 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.
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 northwestern Punjab region: Islamabad is administratively being 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 being annexed by New York City 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).

## Twin cities
### List of International border towns and cities
#### Africa

| Border towns | Countries |
| Kinshasa and Brazzaville | Democratic Republic of the Congo / Republic of the Congo |
| Victoria Falls and Livingstone | Zimbabwe / Zambia |

#### Asia

| Border towns | Countries |
| Astara and Astara | Azerbaijan / Iran |
| Dandong and Sinuiju | China / North Korea |
| Manzhouli and Zabaykalsk | China / Russia |
| Heihe and Blagoveshchensk | China / Russia |
| Dongxing and Mong Cai | China / Vietnam |
| Hekou and Lao Cai | China / Vietnam |
| Johor Bahru and Singapore | Malaysia / Singapore |
| Vientiane and Nong Khai | Thailand / Laos |
| Dansavan and Lao Bao | Laos / Vietnam |
| Al Ain and Al Buraimi | United Arab Emirates / Oman |
| Agartala and Akhaura | India / Bangladesh |
| Eilat and Aqaba | Israel / Jordan |
| Jincheng and Xiamen | Taiwan / China |

#### Europe

| Border towns | Countries |
| Vienna and Bratislava | Austria / Slovakia |
| Bad Radkersburg and Gornja Radgona | Austria / Slovenia |
| Comines and Comines | France / Belgium |
| Mouscron and Tourcoing | France / Belgium |
| Wervik and Wervicq-Sud | France / Belgium |
| Slavonski Brod and Bosanski Brod | Croatia / Bosnia and Herzegovina |
| Český Těšín and Cieszyn | Czech Republic / Poland |
| Copenhagen and Malmö | Denmark / Sweden |
| Valga and Valka | Estonia / Latvia |
| Narva and Ivangorod | Estonia / Russia |
| Imatra and Svetogorsk | Finland / Russia |
| Tornio and Haparanda | Finland / Sweden |
| Strasbourg and Kehl | France / Germany |
| Hendaye and Irun | Spain / France |
| Frankfurt (Oder) and Słubice | Poland / Germany |
| Görlitz and Zgorzelec | Poland / Germany |
| Guben and Gubin | Poland / Germany |
| Heringsdorf and Świnoujście | Poland / Germany |
| Konstanz and Kreuzlingen | Switzerland / Germany |
| Laufenburg (Baden) and Laufenburg, Aargau | Switzerland / Germany |
| Esztergom and Štúrovo | Hungary / Slovakia |
| Komárno and Komárom | Hungary / Slovakia |
| Strabane and Lifford | Ireland / United Kingdom |
| Gorizia and Nova Gorica | Italy / Slovenia |
| Rome and Vatican City | Italy / Vatican |
| Kerkrade and Herzogenrath | Netherlands / Germany |
| La Línea de la Concepción and Gibraltar | Spain / United Kingdom |
| Basel, Weil am Rhein and Saint Louis | Switzerland / Germany / France |
| Tui and Valença | Spain / Portugal |

##### Notes

* ↑ This is an example of capital cities of neighboring nations being twin cities of one another.
* ↑ Separated by the Rhine River (used to be one city until 1801/1802).
* ↑ Vatican City is the only sovereign state surrounded entirely by a single city, Rome. The Vatican is an area in Rome. It was part of Italy until 1929, when Pope Pius XI and Benito Mussolini signed the Lateran Treaty.

#### North America

| Border towns | Bordering countries |
| Niagara Falls, Ontario and Niagara Falls, New York | United States / Canada |
| Sault Ste. Marie, Ontario and Sault Ste. Marie, Michigan | United States / Canada |
| North Portal, Saskatchewan and Portal, North Dakota | United States / Canada |
| Tecate, Baja California and Tecate, California | United States / Mexico |
| Boquillas del Carmen, Coahuila and Boquillas, Texas | United States / Mexico |
| Naco, Sonora and Naco, Arizona | United States / Mexico |
| Nogales, Sonora and Nogales, Arizona | United States / Mexico |
| San Luis Río Colorado, Sonora and San Luis, Arizona | United States / Mexico |
| Nuevo Laredo, Tamaulipas and Laredo, Texas | United States / Mexico |
| Nuevo Progreso, Río Bravo, Tamaulipas and Progreso, Texas | United States / Mexico |
| Calexico, California and Mexicali, Baja California (Calexico–Mexicali) | United States / Mexico |
| Ciudad Hidalgo, Chiapas and Ayutla, San Marcos | Mexico / Guatemala |
| Detroit, Michigan and Windsor, Ontario (Detroit–Windsor) | United States / Canada |
| International Falls, Minnesota and Fort Frances, Ontario | United States / Canada |
| Douglas, Arizona and Agua Prieta, Sonora | United States / Mexico |
| Yuma, Arizona and San Luis Río Colorado, Sonora | United States / Mexico |
| San Diego, California and Tijuana, Baja California see San Diego–Tijuana | United States / Mexico |
| Brownsville, Texas and Matamoros, Tamaulipas see Brownsville–Matamoros | United States / Mexico |
| Del Rio, Texas and Ciudad Acuña, Coahuila | United States / Mexico |
| Eagle Pass, Texas and Piedras Negras, Coahuila | United States / Mexico |
| El Paso, Texas and Ciudad Juárez, Chihuahua see El Paso–Juárez | United States / Mexico |
| Presidio, Texas and Manuel Ojinaga, Chihuahua | United States / Mexico |

#### South America

| Border town | Countries |
| Sant'Ana do Livramento, Rio Grande do Sul and Rivera | Brazil / Uruguay |

### List of internal border towns and cities
#### Africa

| Twin towns | Country |
| Cairo and Giza. Triple cities if counting Shubra El Kheima. | Egypt |
| Port Said and Port Fuad | Egypt |
| Sekondi-Takoradi | Ghana |
| Johannesburg and Pretoria, Gauteng Province | South Africa |

#### Asia

| Twin towns | Country |
| Dhaka and Narayanganj | Bangladesh |
| Guangzhou and Foshan | China |
| Xi'an and Xianyang | China |
| Beijing and Langfang | China |
| Wuxi and Suzhou | China |
| Chaozhou and Shantou | China |
| Haifeng and Lufeng | China |
| Hong Kong and Shenzhen | China |
| Ahmedabad and Gandhinagar, Gujarat | India |
| Allahabad and Naini, Uttar Pradesh | India |
| Bangalore and Hosur, Karnataka | India |
| Bishangarh and Jalore, Rajasthan | India |
| Chümoukedima and Dimapur, Nagaland | India |
| Cuttack and Bhubaneswar, Odisha | India |
| Durg and Bhilai, Chhattisgarh | India |
| Hubli and Dharwad, Karnataka | India |
| Mysore and Srirangapatna, Karnataka | India |
| Kankroli and Rajsamand, Rajasthan | India |
| Kochi and Ernakulam, Kerala | India |
| Coimbatore and Tiruppur, Tamil Nadu | India |
| Kolkata and Howrah, West Bengal | India |
| Mumbai and Navi Mumbai, Maharashtra | India |
| Kalyan and Dombivli, Maharashtra | India |
| Mira and Bhayandar, Maharashtra | India |
| Vasai and Virar, Maharashtra | India |
| Ambarnath and Badlapur, Maharashtra | India |
| Pimpri and Chinchwad, Maharashtra | India |
| Sangli and Miraj, Maharashtra | India |
| Munger and Jamalpur, Bihar | India |
| Noida and Greater Noida, Uttar Pradesh | India |
| Pondicherry and Cuddalore | India |
| Ranchi and Hatia, Jharkhand | India |
| Surat and Navsari, Gujarat | India |
| Sumerpur and Sheoganj, Rajasthan | India |
| Thrissur and Guruvayur, Kerala | India |
| Vijayawada and Guntur, Andhra Pradesh | India |
| Bangarpet and Kolar Gold Fields, Karnataka | India |
| Harihar and Davangere, Karnataka | India |
| Shivamoga and Bhadravati, Karnataka | India |
| Attur and Narasingapuram, Tamil Nadu | India |
| Bhavani and Komarapalayam, Tamil Nadu | India |
| Dharmapuri and Nallampalli, Tamil Nadu | India |
| Erode and Pallipalayam, Tamil Nadu | India |
| Namakkal and Karur, Tamil Nadu | India |
| Tiruchirappalli and Srirangam, Tamil Nadu | India |
| Tirunelveli and Palayamkottai, Tamil Nadu | India |
| Hyderabad and Secunderabad, Telangana | India |
| Asansol and Durgapur, West Bengal | India |
| Barrackpore and Barasat, West Bengal | India |
| Coochbehar and Alipurduar, West Bengal | India |
| Jalpaiguri and Mainaguri, West Bengal | India |
| Siliguri and Jalpaiguri, West Bengal | India |
| Berhampore and Murshidabad, West Bengal | India |
| Erbil and Mosul | Iraq |
| Seleucia and Ctesiphon | Iraq |
| Ramla and Lod | Israel |
| Tel Aviv and Jaffa | Israel |
| Aomori and Hakodate | Japan |
| Kamisu and Kashima | Japan |
| Kitakyushu and Shimonoseki | Japan |
| Kyoto and Otsu | Japan |
| Maebashi and Takasaki | Japan |
| Nasushiobara and Otawara | Japan |
| Okayama and Kurashiki | Japan |
| Osaka and Sakai | Japan |
| Sanjo and Tsubame | Japan |
| Toyohashi and Toyokawa | Japan |
| Tsukuba and Tsuchiura | Japan |
| Yokkaichi and Suzuka | Japan |
| Karagandy and Temirtau | Kazakhstan |
| Beirut and Jounieh, Lebanon | Lebanon |
| Kuala Lumpur and Putrajaya, | Malaysia |
| Bharatpur and Gaindakot | Nepal |
| Butwal and Tilottama | Nepal |
| Nepalgunj and Kohalpur | Nepal |
| Rason and Chongjin | North Korea |
| Jhelum and Sarai Alamgir | Pakistan |
| Peshawar and Mardan | Pakistan |
| Rawalpindi and Islamabad | Pakistan |
| Ramallah and al-Bireh | Palestine |
| Baguio and La Trinidad | Philippines |
| Bantay and Vigan | Philippines |
| Bayombong and Solano | Philippines |
| Dagupan and Lingayen | Philippines |
| Daraga and Legazpi | Philippines |
| Dipolog and Dapitan | Philippines |
| Laoag and San Nicolas | Philippines |
| Lemery and Taal | Philippines |
| Palo and Tacloban | Philippines |
| Santo Tomas and Batangas | Philippines |
| Dammam and Khobar | Saudi Arabia |
| Seoul and Incheon, South Korea | South Korea |
| Busan and Ulsan, South Korea | South Korea |
| Sejong City and Daejeon, South Korea | South Korea |
| Yangyang and Sokcho, South Korea | South Korea |
| Taipei and New Taipei, Taiwan | Taiwan |
| Kaohsiung and Tainan, Taiwan | Taiwan |
| Zhubei and Hsinchu, Taiwan | Taiwan |
| Bangkok and Nonthaburi, Thailand | Thailand |
| Chiang Mai and Lamphun, Thailand | Thailand |
| Songkhla and Hatyai, Thailand | Thailand |
| Ho Chi Minh City and Binh Duong | Vietnam |
| Phan Rang-Tháp Chàm | Vietnam |

##### Historic

| Twin towns | Country |
| Victoria and Kowloon, colonial Hong Kong—although, in both colonial Hong Kong and the Hong Kong Special Administrative Region, Victoria is the only city recognised by law; they were widely considered to be separate cities until at least the mid-1970s. | British Hong Kong |
| Wuhan (merger of Wuchang, Hankou, Hanyang) | China |
| Chirala-Perala | India |
| Bangalore Cantonment and Bengaluru Pete along with their suburbs merged to form modern Bangalore | India |
| Fukuoka (merger of east side of Naka river, Hakata, and the west side, Fukuoka) | Japan |
| Ise (merger of Uji, Yamada) | Japan |
| Joetsu (merger of Takada, Naoetsu) | Japan |
| Naha and Shuri, Okinawa, once separate cities. Shuri became integrated as a district of Naha. | Japan |
| Zhongli and Taoyuan, merged into Taoyuan City. | Taiwan |
| Saigon and Cholon, merged into Saigon-Cholon, now Ho Chi Minh City. | South Vietnam |

#### Europe

| Twin towns | Country |
| Nørresundby and Aalborg | Denmark |
| Kotka and Hamina | Finland |
| Frejus and Saint-Raphaël | France |
| Lyon and Villeurbanne | France |
| Frankfurt and Offenbach | Germany |
| Ludwigshafen and Mannheim | Germany |
| Mainz and Wiesbaden | Germany |
| Mönchengladbach and Rheydt | Germany |
| Nuremberg and Fuerth | Germany |
| Sindelfingen and Böblingen | Germany |
| Ulm and Neu-Ulm | Germany |
| Villingen-Schwenningen | Germany |
| Ballybofey and Stranorlar, in County Donegal, Ireland are often called the Twin Towns and form the built up area of Ballybofey and Stranorlar | Ireland |
| Fredrikstad and Sarpsborg | Norway |
| Porsgrunn and Skien. Together with Tollnes, Gulset and Åfoss they form the Grenland urban area. | Norway |
| Sandnes and Stavanger | Norway |
| Bydgoszcz and Toruń | Poland |
| Kalisz and Ostrów Wielkopolski | Poland |
| Porto and Vila Nova de Gaia | Portugal |
| Póvoa de Varzim and Vila do Conde | Portugal |
| Novi Sad and Petrovaradin, | Serbia |
| Temerin and Bački Jarak | Serbia |
| Zemun and New Belgrade | Serbia |
| Alcobendas and San Sebastián de los Reyes | Spain |
| Aldaia and Alaquàs | Spain |
| Coslada and San Fernando de Henares | Spain |
| Elda and Petrer | Spain |
| Llombai and Catadau | Spain |
| Santa Cruz de Tenerife and San Cristóbal de la Laguna | Spain |
| Jönköping and Huskvarna, | Sweden |
| Donetsk and Makiivka | Ukraine |
| Kramatorsk and Sloviansk | Ukraine |
| Sievierodonetsk and Lysychansk | Ukraine |
| Pokrovsk and Myrnohrad | Ukraine |
| Brighton and Hove | United Kingdom |
| Chatham and Rochester | United Kingdom |
| Leeds and Bradford | United Kingdom |
| Manchester and Salford | United Kingdom |
| Newcastle upon Tyne and Gateshead | United Kingdom |
| Liverpool and Birkenhead | United Kingdom |
| Warwick and Leamington Spa | United Kingdom |

##### Historic

| Twin towns | Country |
| Knokke and Heist-aan-Zee. United into Knokke-Heist | Belgium |
| Gradec and Kaptol. United into Zagreb | Croatia |
| Frýdek and Místek. United into Frýdek-Místek | Czech Republic |
| Barmen and Elberfeld. United into Wuppertal. | Germany |
| Kouvola and Kuusankoski. United into Kouvola. | Finland |
| Äänekoski and Suolahti. United into Äänekoski. | Finland |
| West Berlin, West Germany and East Berlin. United into Berlin. | East Germany |
| Buda and Pest. United into Budapest. | Hungary |
| Bielsko and Biała. United into Bielsko-Biała. | Poland |
| Skanör and Falsterbo. United into Skanör med Falsterbo. | Sweden |
| City of London and City of Westminster. Absorbed into London. | United Kingdom |
| Berwick-upon-Tweed and Tweedmouth, until the former was taken by England from Scotland. | United Kingdom |

#### North America

| Twin towns | Country |
| Halifax and Dartmouth, Nova Scotia | Canada |
| Kitchener and Waterloo, Ontario | Canada |
| Battleford and North Battleford, Saskatchewan "The Battlefords" | Canada |
| Toronto and Mississauga, Ontario | Canada |
| Phenix City, Alabama and Columbus, Georgia | United States |
| Kansas City, Kansas and Kansas City, Missouri | United States |
| Lookout Mountain, Georgia and Lookout Mountain, Tennessee | United States |
| Texarkana, Arkansas and Texarkana, Texas | United States |
| San Bernardino and Riverside, California | United States |
| Fort Collins and Loveland, Colorado | United States |
| Hartford and New Britain, Connecticut | United States |
| Fort Myers and Cape Coral, Florida | United States |
| Fort Lauderdale and Miami, Florida | United States |
| St. Petersburg and Tampa, Florida | United States |
| Augusta, Georgia and North Augusta, South Carolina | United States |
| Boulder and Longmont, Colorado | United States |
| Champaign and Urbana, Illinois | United States |
| Bloomington and Normal, Illinois | United States |
| Lafayette and West Lafayette, Indiana | United States |
| South Bend and Mishawaka, Indiana | United States |
| Waterloo and Cedar Falls, Iowa | United States |
| Bangor and Brewer, Maine | United States |
| Lewiston and Auburn, Maine | United States |
| Benton Harbor and St. Joseph, Michigan | United States |
| Montague and Whitehall, Michigan | United States |
| Houghton and Hancock, Michigan | United States |
| Duluth, Minnesota, and Superior, Wisconsin | United States |
| Minneapolis and Saint Paul, Minnesota | United States |
| Natchez, Mississippi and Vidalia, Louisiana | United States |
| Crystal City and Festus, Missouri | United States |
| New York, New York and Jersey City, New Jersey | United States |
| Raleigh and Durham, North Carolina | United States |
| Winston-Salem and Greensboro, North Carolina | United States |
| Piscataway and New Brunswick, New Jersey | United States |
| Fargo, North Dakota, and Moorhead, Minnesota | United States |
| Grand Forks, North Dakota and East Grand Forks, Minnesota | United States |
| Cincinnati, Ohio and Covington, Kentucky | United States |
| Portland, Oregon and Vancouver, Washington | United States |
| Delmar, Maryland and Delmar, Delaware | United States |
| Scranton and Wilkes-Barre, Pennsylvania | United States |
| Allentown and Bethlehem, Pennsylvania | United States |
| Greenville and Spartanburg, South Carolina | United States |
| Bristol, Tennessee and Bristol, Virginia | United States |
| Memphis, Tennessee and West Memphis, Arkansas | United States |
| Dallas and Fort Worth, Texas | United States |
| Midland and Odessa, Texas | United States |
| Bluefield, Virginia and Bluefield, West Virginia | United States |
| Neenah and Menasha, Wisconsin | United States |
| Marinette, Wisconsin, and Menominee, Michigan | United States |
| Seattle and Tacoma, Washington | United States |
| Wahpeton, North Dakota and Breckenridge, Minnesota | United States |

##### Historic

| Twin city | Country |
| Lloydminster, Alberta/Saskatchewan | Canada |
| Thunder Bay, Ontario | Canada |
| Saginaw and East Saginaw, Michigan | United States |
| Stanwood and East Stanwood, Washington | United States |
| Brooklyn and New York City, New York | United States |

#### South America

| Twin cities | Country |
| Carmen de Patagones and Viedma | Argentina |
| Paraná, Entre Ríos and Santa Fe | Argentina |
| Americana, São Paulo and Santa Bárbara d'Oeste | Brazil |
| Juazeiro and Petrolina | Brazil |
| Olinda and Recife | Brazil |
| Vila Velha and Vitória | Brazil |
| Ponta Porã and Mato Grosso do Sul | Brazil |
| Concepción and Talcahuano | Chile |
| Coquimbo and La Serena | Chile |
| Valparaiso and Viña del Mar | Chile |
| Pedro Juan Caballero and Amambay | Paraguay |
| Callao and Lima | Peru |
| Acarigua and Araure | Venezuela |
| Guarenas and Guatire | Venezuela |

#### Oceania

| Twin city | Country |
| Albury and Wodonga | Australia |
| Canberra and Queanbeyan | Australia |
| Darwin and Palmerston | Australia |
| Forster and Tuncurry | Australia |
| Gold Coast and Tweed Heads | Australia |
| Harden and Murrumburrah | Australia |
| Kalgoorlie and Boulder | Australia |
| Perth and Fremantle | Australia |
| Townsville and Thuringowa | Australia |
| Napier and Hastings | New Zealand |

## Tri-cities

| Border towns | Bordering countries |
| Brisbane; Gold Coast; and Sunshine Coast, Queensland— see South East Queensland | Australia |
| Sydney; Wollongong; and Newcastle, in the geological region known as the Sydney Basin | Australia |
| The Tri-cities of British Columbia consist of Coquitlam, Port Coquitlam, and Port Moody | Canada |
| The Tri-citites of Kitchener; Waterloo; and Cambridge, Ontario, the cities' collective metropolitan area is often called the K-W Tri-City Area | Canada |
| Tri-Town, Ontario- Cobalt, Haileybury and New Liskeard | Canada |
| Xiamen, Quanzhou, Zhangzhou, Fujian | China |
| Wuppertal, Remscheid, Solingen, Rhineland, originally a quad-city until 1929, when Elberfeld and Barmen merged to form Wuppertal | Germany |
| Chandigarh; Mohali; and Panchkula | India |
| Vijayawada; Amaravati; and Guntur | India |
| Chennai,Avadi and Tambaram | India |
| Ranipet, Walajapet and Arcot | India |
| Warangal; Hanamkonda; Kazipet — see Warangal Tri-City | India |
| Kyoto; Osaka; Kobe - see Keihanshin | Japan |
| Parit Buntar, Perak; Nibong Tebal, Penang; and Bandar Baharu, Kedah | Malaysia |
| Guadalajara; Tlaquepaque; Zapopan, Jalisco | Mexico |
| Bhaktapur; Kathmandu; and Patan | Nepal |
| Tricity, consisting of the cities of Baglung, Beni and Kushma | Nepal |
| Bacolod; Silay; Talisay | Philippines |
| Cebu City; Mandaue; and Lapu-Lapu City | Philippines |
| Angeles City; Mabalacat; and San Fernando | Philippines |
| Gdańsk; Gdynia; and Sopot — see Tricity | Poland |
| Wejherowo; Rumia; and Reda — see Kashubian Tricity | Poland |
| The Dammam metropolitan area, consisting of Dammam; Dhahran; and Khobar | Saudi Arabia |
| The metropolitan municipalities of Johannesburg, Tshwane (Pretoria) and Ekurhuleni (East Rand), Gauteng Province | South Africa |
| Gqeberha (Port Elizabeth), Kariega (Uitenhage) and Despatch in Nelson Mandela Bay Metropolitan Municipality, Eastern Cape Province | South Africa |
| East London, Bhisho and Qonce (King William's Town) in Buffalo City Metropolitan Municipality, Eastern Cape Province | South Africa |
| Khartoum; North Khartoum; and Omdurman | Sudan |
| Stockholm; Solna; and Sundbyberg | Sweden |
| Trollhättan; Uddevalla; and Vänersborg | Sweden |
| The Dubai-Sharjah-Ajman metropolitan area, consisting of Dubai; Sharjah; and Ajman, United Arab Emirates | United Arab Emirates |
| Burbank; Glendale; and Pasadena, in Los Angeles County, California | United States |
| Fremont; Newark; and Union City, in Alameda County, California | United States |
| Oceanside; Vista; and Carlsbad, in San Diego County, California | United States |
| Riverside; San Bernardino; and Ontario, California, the cities' collective metropolitan area is often called the Inland Empire | United States |
| San Jose; San Francisco; and Oakland, California | United States |
| College Park; East Point; and Hapeville, Georgia, all of which are near Hartsfield–Jackson Atlanta International Airport | United States |
| 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 | United States |
| Ferrysburg; Grand Haven; and Spring Lake, Michigan | United States |
| Iron River, Caspian, and Gaastra, Michigan | United States |
| Ironwood; Bessemer; and Wakefield, Michigan | United States |
| Grand Island; Kearney; and Hastings, in south-central Nebraska, also known as Tri-Cities, Nebraska | United States |
| Rochester; Dover; and Somersworth, New Hampshire | United States |
| Farmington; Bloomfield; and Aztec, New Mexico | United States |
| Albany, Troy, and Schenectady, New York, in the region known as the Capital District | United States |
| Binghamton; Endicott; and Johnson City, New York, the cities' collective metropolitan area is often called the Triple Cities | United States |
| New York, New York; Newark; and Jersey City, New Jersey | United States |
| Greensboro; Winston-Salem; and High Point, North Carolina, the cities' collective metropolitan area is often called the Piedmont Triad | United States |
| Raleigh; Durham; and Chapel Hill, North Carolina, the cities' collective metropolitan area is often called the Research Triangle | United States |
| Tuttle; Newcastle; and Blanchard, Oklahoma, also known as the Tri-City Area | United States |
| Johnson City; Kingsport; and Bristol, Tennessee/Bristol, Virginia, also known as Tri-Cities, Tennessee | United States |
| Beaumont; Port Arthur; and Orange, Texas, also known as the Golden Triangle (Texas) | United States |
| Dallas; Fort Worth; and Arlington, Texas | United States |
| Petersburg; Colonial Heights; and Hopewell, Virginia, also known as Tri-Cities, Virginia | United States |
| Pasco; Richland; and Kennewick, Washington, also known as Tri-Cities, Washington | United States |
| Washington, D.C., Alexandria, Virginia, and Arlington County, Virginia | United States |

## Quad cities

| Border towns | Bordering countries |
| Xinhui, Taishan, Kaiping, and Enping together formed Siyi area in Jiangmen, Guangdong | China |
| Helsinki, Espoo, Kauniainen and Vantaa in Uusimaa; together form the largest metropolis in the country and its actual capital area. | Finland |
| Pattaya-Chonburi Metropolitan Area consists 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 | Thailand |
| The West Yorkshire Built-up Area consists of the cities of Leeds, Bradford and Wakefield, and the large town of Huddersfield, United Kingdom. | 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. | United States |
| Quad Cities of Davenport and Bettendorf, Iowa, and Rock Island and Moline, Illinois. It also includes a fifth member, East Moline, Illinois. | United States |
| Allentown/Bethlehem, Pennsylvania and Easton, Pennsylvania/Phillipsburg, New Jersey; the collective area is often called the Lehigh Valley | United States |
| The Quad Cities of Minnesota, consist of Virginia, Eveleth, Gilbert, and Mountain Iron. | United States |
| The cities of Pullman, Washington, Moscow, Idaho, Lewiston, Idaho and Clarkston, Washington, have marketed themselves as "Quad Cities." | United States |

## More than four cities

| Border towns | Country |
| The Triangle Region, consisting of Billund, Fredericia, Haderslev, Kolding, Middelfart, Vejen and Vejle. | Denmark |
| The Ruhr district consisting of Dortmund, Essen, Duisburg, Bochum, Oberhausen, Mülheim, Bottrop, Gelsenkirchen and Herne in its core. | Germany |
| The cities of New Delhi, Noida, Greater Noida, Ghaziabad, Gurgaon and Faridabad have formed a huge metropolitan area known as National Capital Region (India). | India |
| 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. | India |
| 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. | Malaysia |
| 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). | Kazakhstan |
| 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. | United States |
| 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. | United States |
| Virginia: Norfolk, Chesapeake, Hampton, Newport News, Portsmouth, Suffolk, and Virginia Beach; the cities' collective metropolitan area is often called Hampton Roads | United States |

## 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.
    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.
    The Netherlands
   * Eindhoven, the Netherlands, merged with five neighbouring municipalities (Woensel, Tongelre, Stratum, Gestel en Blaarthem and Strijp) into the new Groot-Eindhoven ("Greater Eindhoven") in 1920. The prefix "Groot-" was later dropped.
    Spain
   * Madrid, evolved by absorption of other towns (like Tetuán de las Victorias, Vallecas, Chamartín de la Rosa or Aravaca)
    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.
   * 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 Verrazano-Narrows Bridge.
* Helium, from the Barsoom series of novels by Edgar Rice Burroughs, consists of the twin cities Greater Helium and Lesser Helium.