sister-city relationship
Refers to the formal affiliation between two cities, often involving cultural or economic exchange.
The two cities have a sister-city relationship.
姉妹都市 is the more common term for 'sister city'; 姉妹友好都市関係 is a longer, more formal expression emphasizing the friendly relationship.
Standard kanji form for this compound noun.
Variant with interpunct, sometimes used for clarity.
Compound of 姉妹 (sisters), 友好 (friendship), 都市 (city), and 関係 (relationship).