Leach Highway is a east-west arterial highway in the southern suburbs of Perth, Western Australia, primarily linking Kewdale and Perth Airport with the city of Fremantle. It is allocated State Route 7 and is a dual carriageway for its entire length. Leach Highway varies in width between four and six lanes, with speed limits of . Route description Leach Highway is one of the state's most important heavy vehicle routes. It links the major industrial areas of Kewdale and Welshpool with Western Australia's major container port at Fremantle. Although the Leach Highway's western terminus is at Carrington Street in Palmyra, High Street continues for a further into Fremantle, and connects it to the Stirling Highway. History Leach Highway is named for Leach, former Commissioner of Main Roads Western Australia. Construction began in 1966, with the first section opened between its present western terminus at Carrington Street, Melville (now Palmyra), and High Road in Canning (now Willetton) in 1972. It was soon extended eastward from High Road through to Manning Road, utilising the old timber Riverton Bridge over the Canning River via Barbican Street East and what is now Fern Road and Grayson Court. In 1976 it was further extended from Manning Road to Orrong Road, including bridges over Albany Highway in Bentley and the Armadale railway line in Welshpool. Then in 1978 the 4-lane concrete Shelley Bridge over Canning River opened, with Riverton Bridge retained for local traffic. In the early 1980s the highway was extended further eastward, first to Hardey Road and, soon thereafter, to the new Beechboro-Gosnells Highway (now called Tonkin Highway) which remains as the highway's present eastern terminus. Also around that time a number of intersections were built to coincide with new roads being built around Leach Highway. A parclo interchange was constructed at the newly extended Kwinana Freeway, and an intersection was constructed for the new Centenary Avenue in Wilson to improve access to the Western Australian Institute of Technology (WAIT), now called Curtin University. New at-grade intersections were built at Murdoch Drive and Winthrop Drive to service the new suburbs of Bateman and Winthrop. Although not strictly Leach Highway, in 1985 Stirling Highway was extended southwards from its then terminus at Canning Highway to a new terminus at High Street (an extension of Leach Highway). This marked the final piece of an improved freight link between the Port of Fremantle and Perth's major industrial