Poznań (; German: Posen, known also by other historical names) is a city on the Warta river in west-central Poland, in the Greater Poland region. It is best known for its renaissance Old Town and Ostrów Tumski Cathedral. Today, Poznań 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. Poznań is among the oldest and largest cities in Poland. The city population is about 550,000, while the continuous conurbation with Poznań County and several other communities is inhabited by almost 1.1 million people. The Larger Poznań Metropolitan Area (PMA) is inhabited by 1.3–1.4 million people and extends to such satellite towns as Nowy Tomyśl, Gniezno and Września, making it the fourth largest metropolitan area in Poland. It is the historical capital of the Greater Poland region and is currently the administrative capital of the province called Greater Poland Voivodeship. Poznań is a centre of trade, sports, education, technology and tourism. It is an important academic site, with about 130,000 students and the Adam Mickiewicz University - the third largest Polish university. Poznań is also the seat of the oldest Polish diocese, now being one of the most populous archdioceses in the country. The city also hosts the Poznań International Fair – the biggest industrial fair in Poland and one of the largest fairs in Europe. The city's most renowned landmarks include Poznań Town Hall, the National Museum, Grand Theatre, Poznań Cathedral and the Imperial Castle. Poznań has often topped rankings as a city with very high quality of education and a very high standard of living. It also ranks highly in safety and healthcare quality. The city of Poznań has also won many times a prize awarded by "Superbrands" for a very high quality city brand. Poznań was classified in 2012 as high sufficiency city by Globalization and World Cities Research Network. In 2012, the Poznań's Art and Business Center "Stary Browar" won a competition organised by National Geographic Traveller and was given the first prize as one of the seven "New Polish Wonders". The official patron saints of Poznań are Saint Peter and Paul of Tarsus, the patrons of the cathedral. Martin of Tours – the patron of the main street Święty Marcin is also regarded as one of patron saints of the city.