Belgium–France border Comines, Belgium and Comines, France Mouscron, Belgium and Tourcoing, France Wervik, Belgium and Wervicq-Sud, France Croatia–Bosnia and Herzegovina border Slavonski Brod, Croatia and Bosanski Brod, Bosnia and Herzegovina Czech Republic–Poland border Těšín, Czech Republic and Cieszyn, Poland Denmark–Sweden border Copenhagen, Denmark and Malmö, Sweden Estonia–Latvia border Valga, Estonia and Valka, Latvia Estonia–Russia border Narva, Estonia and Ivangorod, Russia Finland–Russia border Imatra, Finland and Svetogorsk, Russia Finland–Sweden border Tornio, Finland and Haparanda, Sweden France–Germany border Strasbourg, France and Kehl, Germany France–Spain border Hendaye, France and Irun, Spain Germany–Poland border Frankfurt (Oder), Germany and Słubice, Poland Görlitz, Germany and Zgorzelec, Poland Guben, Germany and Gubin, Poland Heringsdorf, Germany and Świnoujście, Poland Germany–Switzerland border Konstanz, Germany and Kreuzlingen, Switzerland Laufenburg (Baden), Germany and Laufenburg,_Aargau, Switzerland, separated between the Rhine River (used to be one city until 1801/1802). Hungary–Slovakia border Esztergom, Hungary and Štúrovo, Slovakia Komárno, Slovakia and Komárom, Hungary Ireland–United Kingdom border Strabane, Northern Ireland and Lifford, Ireland Italy–Slovenia border Gorizia, Italy and Nova Gorica, Slovenia The Netherlands–Germany border Kerkrade, The Netherlands and Herzogenrath, Germany Spain–Gibraltar border La Línea de la Concepción, Spain and Gibraltar Switzerland–Germany-France border Basel, Switzerland and Weil am Rhein, Germany and Saint Louis, France Historic 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, Germany. United into Wuppertal. West Berlin, West Germany and East Berlin, East Germany. United into Berlin, Germany. Buda and Pest. United into Budapest, Hungary. Bielsko and Biała, Poland. United into Bielsko-Biała. City of London and City of Westminster, England. Absorbed into London, United Kingdom. Berwick-upon-Tweed and Tweedmouth, until the former was taken by England from Scotland. Oceania 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 Napier and Hastings, New Zealand Perth and Fremantle, Australia Townsville and Thuringowa, Australia Tri-cities Australia Brisbane; Gold Coast; and Sunshine Coast, Queensland, Australia — see South East Queensland Sydney; Wollongong; and Newcastle, Australia in the geological region known as the Sydney Basin Canada The Tri-cities of British Columbia consist of Coquitlam, Port Coquitlam, and Port Moody The Tri-citites of Kitchener; Waterloo; and Cambridge, Ontario, Canada, the cities' collective metropolitan area is often called the K-W Tri-City Area Tri-Town, Ontario, Canada - Cobalt, Haileybury and New Liskeard China Xiamen, Quanzhou, Zhangzhou,