The Hume Highway, inclusive of the sections now known as the Hume Freeway and Hume Motorway, is one of Australia's major inter-city national highways, running for 840 kilometres (520 mi) between Melbourne in the southwest and Sydney in the northeast. Upgrading of the route from Sydney's outskirts to Melbourne's outskirts to dual carriageway was completed on 7 August 2013. From north to south, the road is called the Hume Highway in metropolitan Sydney, the Hume Motorway between the suburbs of Edmondson Park and Prestons and Berrima, the Hume Highway elsewhere in New South Wales and the Hume Freeway in Victoria. It is part of the Auslink National Network and is a vital link for road freight to transport goods to and from the two cities as well as serving Albury-Wodonga and Canberra.
In New South Wales during 2013, the National Highway shield, National Highway 31, was replaced with a standard alphanumeric route number, the M31 south of Prestons (along with the A22 east of Liverpool into the Sydney CBD and the A28 for a short length through Liverpool). This re-numbering for the first time in over 20 years created one continuously signed route along the Hume Highway, having already been signed the M31 in Victoria during the 1990s. During 2013, the route between Berrima and Prestons was also renamed the Hume Motorway.