Uusikaupunki (Finnish: [ˈuːsiˌkɑu̯puŋki] ; Swedish: Nystad, Finland Swedish: [nyːstɑːd]; also known as Vasaborg) is a town and municipality of Finland. It is located in the Southwest Finland region, 71 kilometres (44 mi) northwest of Turku and 97 kilometres (60 mi) south of Pori. The municipality has a population of 14,750 (30 June 2025) and covers an area of 551.65 square kilometres (212.99 sq mi) of which 49.04 km (18.93 sq mi) is inland water. The population density is 29.31 inhabitants per square kilometre (75.9/sq mi).
The municipality is unilingually Finnish. Both its Finnish and Swedish names translate literally to "new town". The original name of the main village that was incorporated into Uusikaupunki was Kalainen (roughly translated from Finnish as "rich in fish"). The surrounding region, and especially the neighboring town of Kalanti, which merged with Uusikaupunki in 1993, was already a lively marketplace for wooden objects and salt in the early Middle Ages. Uusikaupunki was founded to legalize this trade.
