Karlovac is a city and municipality in central Croatia. According to the preliminary results of the National census held in 2011 the city proper has a population of 46,827, while the municipality has a population of 55,981 inhabitants. Karlovac is the administrative centre of Karlovac County. The city is located on the Zagreb-Rijeka highway and railway line, 56 km south-west of Zagreb and 130 km from Rijeka.
The city was named for the Archduke of Austria Charles II, which in German is Karlstadt or Carlstadt ("Charles's Town"). It has then been translated into other languages: in Hungarian it is known as Károlyváros, in Italian as Carlostadio, in Latin as Carlostadium.