Poznań (Polish: [ˈpɔznaɲ]) is a city on the River Warta in west-central Poland, within the Greater Poland region. The city is an important cultural and business centre, and one of Poland's most populous regions with many regional customs such as Saint John's Fair (Jarmark Świętojański), traditional Saint Martin's croissants and a local dialect. Among its most important heritage sites are the Renaissance Old Town, Town Hall and Gothic Cathedral.