Road routes in New South Wales assist drivers navigating roads throughout the state, as roads may change names several times between destinations, or have a second local name in addition to a primary name. New South Wales previously used an older, numerical shield-based system (which this article focuses on) until 2013, when it was completely replaced (except for Tourist Routes) with a newer, alphanumeric system.
New South Wales implemented the federally-issued National Routes system between 1954 and 1955, using white-and-black shields highlighting interstate links between major regional centres; some of these routes were later upgraded into National Highways using green-and-gold shields when the National Roads Act was passed in 1974.
Sydney's initial shield system was the Ring Road system, with three routes rolled out in 1964. These were eventually replaced by a specialised Freeway Routes system in 1973, and a state-wide shield-based numbering scheme, allocating blue-and-white shields across Sydney in 1974, numbered to fit around existing National Routes, with separate allocations for rural New South Wales, the Hunter (Greater Newcastle) and Illawarra (Greater Wollongong) regions; this system received sporadic updates throughout the 1990s and 2000s. These were augmented by the Metroad system in 1992-3, with its blue-on-white hexagonal shields identifying major routes through Sydney, with additional routes added through the late 1990s.
The new alphanumeric system, introduced in 2013, has now replaced the previous scheme across the entire state. It consists of alphanumeric routes, a one-to-three digit number prefixed with a letter (M, A, B, or D) that denotes the grade and importance of the road, and (apart from Tourist Routes) is now the state's only road route numbering system.
Some routes, in part or in their entirety, may have been made obsolete by the alphanumeric designation: these replacement routes are noted but not listed in full here. Some also may follow older alignments or routes later changed even after the new system was introduced, and are included here for the sake of completion. Roads are described in either a west-east or north–south alignment.
National Routes
National Routes were the first type of route numbering to be attempted in Australia on a large scale, signed with a white shield and black writing (similar in shape to the shield that appears on the Australian coat of arms), with New South Wales receiving routes in 1954. They highlighted the interstate links connecting major population, industrial and principal regions of New South Wales to the rest of the Australia, in a way that was readily identifiable to interstate travellers. The system was prepared by COSRA (Conference of State Road Authorities), held between 1953-4: once each state road authority agreed to the scheme, it was rolled out federally.
In 1954, the Hume Highway was trialled as National Route 31, chosen due to its prominence as a transport corridor connecting Australia's largest cities (Sydney and Melbourne). Soon after, other National Routes across the state were allocated. Selected routes were later upgraded into National Highways when the National Roads Act was passed in 1974.
New South Wales' National Routes were initially replaced within the boundaries of Sydney with the Metroad system in 1992-3, and eventually replaced entirely across the state by the alphanumeric system in 2013: each route was converted to an alphanumeric route number, rendering the previous shields redundant. Many National Routes across New South Wales were renumbered during the conversion, while some others were not replaced at all and became unsigned.
National Highways
With the passing of the National Roads Act in 1974, selected National Routes were further upgraded to the status of a National Highway: interstate roads linking Australia's capital cities and major regional centres that received federal funding, and were of higher importance than other National Routes. These new routes were symbolised by green shields with gold writing, and the word "National" along the top of the shield. Most of New South Wales' National Highways were declared in 1974 and their shields converted in the following years, with National Highways 20 and 39 later declared in 1992.
Like National Routes, New South Wales' National Highways were also replaced with the alphanumeric system, introduced across the state in 2013: each route was converted to an alphanumeric route number, with all keeping their number during the conversion.