The Belgrade-Bar railway is a standard-gauge railway, long. Of this length, of the railway goes through Serbia, and through Montenegro. It is electrified with 25 kV, 50 Hz AC along the entire corridor. It passes through 254 tunnels of total length of and over 435 bridges (total length ). The longest tunnels are Sozina, , and Zlatibor, . The biggest and the best known bridge is Mala Rijeka Viaduct, long and above ground level.