Princes Highway, Dandenong and Bass Highway opened in the early 1990s between Princes Highway and Pound Road. The South Gippsland Highway was signed as State Route 180 between Dandenong and Sale on 13 December 1985, the first road in Victoria signed with a State Route; with Victoria's conversion to the newer alphanumeric system in the late 1990s, this was replaced by route M420 between Lynbrook and Lang Lang, and B440 between Lang Lang and Sale (which was upgraded to A440 when highway upgrades along South Gippsland Highway raised the quality of the road in 2003). Timeline of upgrades and duplication 1961 – Whitelaw By-pass Road: 2.5 miles just north of Korumburra completed as a 2-lane, single-carriageway road, replacing a narrow winding route 3.5 miles long consisting of portions of Bena-Korumburra and Warragul-Korumburra Roads, eliminating two railway crossings, costing A£65,000. 1975 – Conversion to dual carriageways at the western end began in 1975, between the South Gippsland Freeway and Cranbourne; a distance of 17 km. 1987 – Duplication works completed on three sections. Cranbourne to Five Ways, Tooradin to Dalmore Road, and Monomeith Road to Bass Highway. 1989 – 3 km of dual carriageways opened between Manks Road and Lynes Road, Tooradin in December 1989. 1990 – 3 km of dual carriageways opened between Lynes Road, Tooradin and Dore Road in April 1990. At this stage, ’27 km of the planned 32 km length of duplication between Cranbourne and Bass Highway has now been completed’. 1990/1991 – Duplication of 6 km south of Tooradin completed at a cost of $A9.9m. No exact date was given, however VicRoads Annual Reports cover the previous financial year. This completed the duplication of the highway between Cranbourne and the Bass Highway. An interesting anomaly is that the kilometre lengths quoted in this annual report and the previous annual report do not match! 1991/1992 – 2.8 km duplication opened between Princes Highway and Pound Road. This was the final link in the duplication of the highway from the Princes Highway to Bass Highway, Again, no exact date was given, however VicRoads Annual Reports cover the previous financial year. Level crossing elimination The Gippsland railway line crossing just south of the intersection with Princes Highway in Dandenong South was removed in 3 August 2021. The contract was awarded in March 2020, with construction starting in October 2020 on a new road bridge over the rail line on