|Part of E70|
|Length:||92.5 km (57.5 mi)|
|From:||Croatian A3 at Batrovci broder crossing|
|To:||(Belgrade bypass) at Dobanovci interchnage|
|Major cities:||Sremska Mitrovica, Ruma, Belgrade|
|Highways in Serbia|
The A3 motorway in Serbia spans approximately 92 kilometers (57 mi) and is part of the Pan-European Corridor X through Serbia. It crosses the Srem region from east to west, starting at Batrovci border crossing with Croatia and ending at Belgrade bypass (A1 motorway) on Dobanovci interchange.
The Batrovci–Belgrade section is part of the old Belgrade-Zagreb highway, known as Highway "Brotherhood and Unity" in the socialist era. It is a continuation to Croatian A3 highway, whose last section, from Slavonski Brod to Lipovac was completed to four lanes in 2006. From the Lipovac–Batrovci border crossing near Šid, it continues eastwards, along the towns of Sremska Mitrovica, Ruma and Stara Pazova. Belgrade's Nikola Tesla Airport lies on the southern side of the highway. Few kilometers on the east, the major Dobanovci interchange is located. Currently, it only branches southwards, across the Ostružnica bridge towards the Ibarska highway, but after completion of the Belgrade beltway it will link the A3 with the northern and southern branches of the A1 motorway (Subotica–Belgrade–Niš), allowing transit traffic to bypass Belgrade. The highway continues as a motorway through Belgrade (as currently non-designated route) and enters the New Belgrade and Zemun outskirts. It crosses the Sava river at the Gazela bridge.
The main toll stations of the A3 are located near Batrovci and Stara Pazova (Šimanovci). The section from Šimanovci to Belgrade is toll-free.
The Belgrade-Zagreb highway was built after the World War II, by the young volunteers, and opened on 28 July 1950, first as a single carriageway. The second carriageway from Šid to Belgrade was completed in 1987.