Highways in Serbia

Roads in Serbia are the backbone of its transportation system and constitute important transit roads in Europe. Total length of roads in the country is 45,419 km, and they are categorized as "state roads" (with total length of 16,179 km) or "municipal roads" (with total length of 23,780 km).

Major roads in the country are designated as "state roads", all of which are paved. They are categorized as: state roads, class Ia; state roads, class Ib; state roads, class IIa; and state roads, class IIb.

Roads that are motorways are categorized as state roads, class Ia and are marked with one-digit numbers (as the Serbian word for motorway is "autoput", the "A1", "A2", "A3", "A4" or "A5" road designations are used). As of September 2017, there are 782 km of motorways (Serbian: аутопут, аutoput) in total. Motorways in Serbia have three lanes (including emergency lane) in each direction (including hard shoulder), signs are white-on-green, and the normal speed limit is 120 km/h.

Roads categorized as state roads, class Ib are 4,481 km in total length and are marked with two-digit numbers. They have one lane at the each direction, signs are black-on-yellow and the normal speed limit is 80 km/h.

Some of these roads are or will be partially expressways (Serbian: Брзи пут, Brzi put), such as 24 km-long stretch of State Road 24 between Kragujevac and Batočina (intersection with A1 motorway) and planned upgrade of the 27 km-long section of State Road 21 between Novi Sad and Ruma (intersection with A1 motorway). Expressways, unlike motorways, don't have emergency lanes, signs are white-on-blue and the normal speed limit is 100 km/h.

State roads, class IIa, are marked with three-digit numbers, first digit being 1 or 2. Total length of these roads is 7,781 km.

State roads, class IIb, are marked with three-digit numbers, first digit being 3. Total length of these roads is 3,160 km.

Minor, local roads in the country are designated as "municipal roads". Total length of these roads is 23,780 km and some two-thirds are paved roads, while the rest are consisted of macadam and earthen roads.

...
Wikipedia