twin town
From Longman Dictionary of Contemporary Englishtwin townˌtwin ˈtown noun [countable] British EnglishPGTOWN a town that has formed a relationship with a similar town in another country in order to encourage visits between them Oxford’s twin town is Bonn. → twin3(1)Examples from the Corpustwin town• A choir is raising money to fund a trip to Reutlingen, twin town of Ellesmere Port and Neston.• The initiative is part of Durham's appeal for food and medical aid for the county's twin town of Kostroma.