Transport in Zagreb, the capital of Croatia, relies on a combination of city-managed mass transit and individual transportation. Mass transit is composed of 19 inner-city tram lines and 120 bus routes, both managed entirely by Zagrebački električni tramvaj. Croatian Railways manages the parallel Zagreb Commuter Rail system. The city is served by the Franjo Tuđman Airport, which carries more than 2,500,000 passengers per year.
Zagreb drivers typically use a wide network of avenues and other arterial streets. Due to the shape of the city, most of the trips done in the city are on the east-west relation, causing high traffic on roads like Vukovar Avenue, Dubrovnik Avenue and Zagrebačka Avenue. The 18-kilometer (11 mi) Slavonska Avenue is the longest and one of the most congested roads in Zagreb, connecting the inner city to the A3 highway in the east.
Zagreb is a regional highway hub with eight highways and expressways radially leading into the city through the Zagreb bypass. Major highways and expressways include A1/A6, leading to Gorski Kotar, the Littoral and Dalmatia; A3 leading west to Rakitje, Samobor, Žumberak and Slovenia and east to Rugvica, Ivanić-Grad, Slavonia and Serbia; A2 leading northwest to Zaprešić, Zabok, Krapina and Central Europe; A4 leading northeast to Varaždin, Čakovec, Hungary and on to Eastern Europe; A11 leading southeast to Velika Gorica, Sisak and Petrinja (still in construction) and D10 leading east to Vrbovec and Križevci.