A6 (Croatia)

The A6 motorway (Croatian: Autocesta A6) is a motorway in Croatia spanning 80.2 kilometres (49.8 mi). It connects the nation's capital, Zagreb, via the A1, to the seaport of Rijeka. The motorway forms a major north–south transportation corridor in Croatia and is a part of European route E65 Nagykanizsa–Zagreb–Rijeka–Zadar–Split–Dubrovnik–Podgorica. The A6 motorway route also follows Pan-European corridor Vb.

The A6 motorway runs near a number of Croatian cities, provides access to Risnjak National Park and indirectly to numerous resorts, notably in the Istria and Kvarner Gulf regions. The motorway route was completed in 2008. The motorway is nationally significant because of its positive economic impact on the cities and towns it connects, and because of its contribution to tourism in Croatia. The importance of the motorway as a transit route will be further increased upon completion of a proposed expansion of the Port of Rijeka and Rijeka transport node.

The motorway consists of two traffic lanes and an emergency lane in each driving direction separated by a central reservation. Sections of the motorway that have a gradient greater than 4% are divided into three lanes to prevent traffic problems caused by slower vehicles. These sections have no emergency lanes. Similarly, there are no emergency lanes in the tunnels. All intersections of the A6 motorway are grade separated. As the route traverses rugged mountains it requires numerous long bridges, viaducts, tunnels, and other structures. As of 2010 there are nine exits and three rest areas situated along the route. The majority of the motorway is a ticket system toll road with pricing tied to vehicle classification. Each exit between Grobnik mainline toll plaza and Bosiljevo 2 interchange has a toll plaza. No toll is charged at Bosiljevo 2 where the traffic switches to the A1 motorway; traffic is tolled upon leaving the A1 motorway. Exits between the mainline toll plaza and Orehovica interchange have no toll plazas, as that part of the A6 route is not tolled.

A motorway connecting Zagreb and Rijeka was originally designed in the early 1970s, and construction started north of Rijeka and south of Zagreb. The first section, between Rijeka and Kikovica, opened on September 9, 1972, and a Zagreb–Karlovac section followed on December 29, 1972. Those sections were the first modern motorways to be built in Croatia and Yugoslavia. Due to political upheavals in Croatia and Yugoslavia, construction of the motorway was labeled a "nationalist project" and, along with the proposed Zagreb–Split motorway, was cancelled in 1971. After the Croatian War of Independence, efforts to build the motorway were renewed and construction resumed in 1996. In 2004, a two-lane, single carriageway expressway was completed between the sections completed 25 years previously, and the second carriageway was built; the motorway was completed on October 22, 2008. Construction costs are estimated at 661.5 million euro. Although Hrvatske autoceste normally designs, builds, and operates motorways in Croatia, the A6 motorway is operated and maintained by Autocesta Rijeka – Zagreb.