South Road and its southern section as Main South Road outside of Adelaide is a major north–south conduit connecting Adelaide and the Fleurieu Peninsula, in South Australia. It is one of Adelaide's most important arterial and bypass roads. As South Road, it is designated part of route A2 within suburban Adelaide. As Main South Road, it is designated part of routes A13 and B23. The northern part of South Road contributes the central component of the North–South Corridor, a series of road projects under construction or planning that will eventually provide a continuous expressway between Old Noarlunga and Gawler. Route South Road starts at the intersection of the Port River Expressway and the Salisbury Highway in Wingfield. It runs directly south, through much of Adelaide's inner western suburbs, close to the Adelaide city centre. It is complimented by, and in some instances, subsumed into the North-South Motorway. It either runs directly underneath it at ground level with the motorway above it on elevated carriageways, or straddles it on each side with the motorway lowered into a trench. The motorway currently ends in Hindmarsh just south of the intersections with Port Road and Grange Road. South Road then becomes the main traffic route southwards. South Road continues south through Mile End and Edwardstown until St Marys, where the Southern Expressway starts in a lowered trench. South Road straddles it on each side, until it reaches the intersection of Ayliffes and Shepherds Hill Roads at Tonsley, South Australia, where it changes name to Main South Road. It continues through Old Noarlunga (where Victor Harbor Road branches off) and runs parallel to the coastline of Gulf St Vincent. At Normanville, it is known as Willis Drive for 2 km, then continues to Cape Jervis at its southern tip. The Southern Expressway runs roughly parallel to Main South Road for 18 km between Darlington and Noarlunga and serves to reduce traffic congestion. Main South Road and the Southern Expressway have 3 different intersections along the length of the roads. History The first reference to South Road was made in 1842. The South Australian Gazette referred to sheep stations near the corner of South Road and Sturt Road, in what is now Bedford Park. South Road of today was until the 1970s known by a string of names: Shillabeer Avenue (from what was then its northern terminus at Regency Road to Torrens Road); Government Road