Rijeka (Croatian: [rijěːka] ; Fiume [ˈfjuːme] in Italian and Fiuman Venetian) is the principal seaport and the third-largest city in Croatia. It is located in Primorje-Gorski Kotar County on Kvarner Bay, an inlet of the Adriatic Sea and in 2021 had a population of 107,964 inhabitants. Historically, because of its strategic position and its excellent deep-water port, the city was fiercely contested, especially between the Holy Roman Empire, Venice, Italy and Yugoslavia, changing rulers and demographics many times over centuries. According to the 2021 census data, 85% of its citizens are Croats, along with small numbers of Serbs, Bosniaks and Italians.
Rijeka is the main city and county seat of the Primorje-Gorski Kotar County. The city's economy largely depends on shipbuilding (shipyards 3. Maj and Viktor Lenac Shipyard) and maritime transport. Rijeka hosts the Croatian National Theatre Ivan pl. Zajc, first built in 1765, as well as the University of Rijeka.
