Mallee Highway

Mallee Highway is a highway connecting Tailem Bend in south-eastern South Australia and Piangil in north-western Victoria, running mostly across the Mallee plains. It forms part of the shortest route between Adelaide and Sydney.

Route
Mallee Highway commences at the intersection with Dukes Highway just south-east of Tailem Bend in South Australia and runs east as a dual-lane, single-carriageway road, through cereal-growing farmland at the southern end of the Murray Mallee to Pinnaroo near the border with Victoria, where it crosses the Ngarkat and Browns Well Highways. It continues east into Victoria through Murrayville and Walpeup until it reaches Ouyen, where it meets Calder Highway, then continues east through Manangatang to Piangil, where it meets with Murray Valley Highway, then along Tooleybuc Road two kilometres to the north where it continues east until it eventually terminates at the New South Wales border and the Murray River at Tooleybuc, where the highway officially ends; the road continues through New South Wales eventually to meet Sturt Highway at Balranald.

History
Within Victoria, the passing of the Country Roads Act of 1912 through the Parliament of Victoria provided for the establishment of the Country Roads Board (later VicRoads) and their ability to declare Main Roads, taking responsibility for the management, construction and care of the state's major roads from local municipalities. Ouyen-Pinnaroo Road was declared a Main Road from Ouyen via Walpeup Murrayville to the state border with South Australia on 14 December 1914.

The passing of the Highways and Vehicles Act of 1924 provided for the declaration of State Highways, roads two-thirds financed by the State government through the Country Roads Board. Ouyen Highway was declared a State Highway within Victoria in the 1947/48 financial year, from Calder Highway at Ouyen via Murrayville and Walpeup to the border (for a total of 81 miles), subsuming the original declaration of Ouyen-Pinnaroo Road as a Main Road.

With the passing of the Transport Act of 1983, the highway was renamed as Mallee Highway, and extended east along the former Ouyen–Piangil Road and Tooleybuc Road to Piangil in December 1990.

The highway was signed as National Route 12 between Tailem Bend and Ouyen in 1955, later extended with the road to Piangil in 1990. With both states' conversion to their newer alphanumeric systems in the late 1990s, its former route number was updated to B12 in 1997 (within Victoria), and in 1998 (in South Australia).

The passing of the Road Management Act 2004 granted the responsibility of overall management and development of Victoria's major arterial roads to VicRoads: in 2004, VicRoads re-declared the road as Mallee Highway (Arterial #6650), beginning at the South Australian border at Panitya and ending at the New South Wales border in Piangil.