The highway begins at Kwinana Freeway's southern terminus in Ravenswood, continues around the Peel Inlet to Lake Clifton, and heads south to finish at Bunbury's Eelup Roundabout.

The settlement of Australind by the Western Australian Land Company in 1840–41 prompted the first real need for a good quality road to Perth.

Within one year of opening, the number of road accidents in the area had decreased significantly, but tourism and businesses in the towns on bypassed routes were also affected.

[2] The southern portion of the road going past Australind into Bunbury was later bypassed by the Wilman Wadandi Highway when that was opened in December 2024.

Forrest Highway is the southern section of State Route 2, continuing south from Kwinana Freeway at a folded diamond interchange with Pinjarra Road.

[3] The highway, which is controlled and maintained by Main Roads Western Australia,[4] has two lanes in each direction separated by a wide median strip,[3] and a speed limit of 110 kilometres per hour (70 mph).

Forrest Highway meanders across the Spearwood dune system[5] for ten and a half kilometres (6.5 mi), through a series of large curves, before it reaches Old Coast Road at Lake Clifton, an alternative coastal route to Mandurah.

The last stretch of approximately 19 kilometres (12 mi) was the most dangerous for many years, as it required precarious crossings at the Collie and Preston Rivers.

[11]: 1–2 In an initial attempt to settle the area, the government declared the land open for pastoral settlement by ordinary settlers, but little progress was made.

[11]: 2  The settlement of Australind by the Western Australian Land Company in 1840–41 prompted the first real need for a good quality road to Perth.

[11]: 5–6 In a letter dated 12 June 1842 in the Colonial Secretary's Records, Marshall Waller Clifton, Chief Commissioner of the Western Australian Land Company, wrote of the need for an improved Perth–Fremantle–Bunbury road.

Governor John Hutt approved of the idea of a road, but thought a ferry would be impractical, at least during winter, and that the lack of public funds made it impossible.

[28] By 1943, vegetation was overgrowing the road, making it difficult to spot in places,[29] and in December 1946 about 200 yards (180 m) was inundated by water one-foot (30 cm) deep.

[32] At a February 1949 conference of officials from local governments in the South West region it was decided to once more pursue the reopening of the coastal route, due to the amount of traffic on the existing Perth–Bunbury road.

[36] Reasons for supporting the proposal included "defence, land settlement, relieving the main highway, and tourist advantages".

The summer of 1950 had seen a shortage of milk in Perth, leading to the consideration of turning undeveloped land along Old Coast Road into pastures for dairy farming.

The old wooden bridge had rapidly deteriorated due to the presence of marine organisms, and needed considerable attention to maintain it in a usable condition.

The opening ceremony was attended by the Chairman of the Mandurah Road Board, W. Anderson, Leader of the Opposition, Ross McLarty, Minister for Works, John Tonkin; Commissioner of Main Roads, Digby Leach; C. H. Henning, MLC; engineer in charges of bridges, Ernest Godfrey; local government representatives, and a number of schoolchildren who were given a half-day off school.

The bypass travelled to the east and south of Australind and Eaton, to connect to Bunbury's Eelup Roundabout via an alignment previously part of Jubilee Road.

[57] Australind Bypass was opened on 16 December 1988[60]: 359  by Federal Transport Minister Bob Brown, who helped complete the final seal, together with the Mayor of Bunbury Ern Manea.

[57] The new road was designed to be easily made into a dual carriageway when required;[57] this was completed nine years later, with the Australind Bypass duplication project officially opened by Mitchell MLA Dan Sullivan on 18 December 1997.

[63] While Old Coast Road's dual carriageway was advancing north from Bunbury, and Kwinana Freeway was progressively being extended south from Perth, the alignment through Mandurah was constrained by existing development.

The relevant environment factors considered by the EPA were vegetation communities, declared rare and priority flora, wetlands, and traffic noise.

To minimise impact, road drainage would be designed to contain spills and prevent direct discharges into the surrounding environment.

The work was undertaken by a partnership of Main Roads, Leighton Contractors, WA Limestone and GHD, known as the Southern Gateway Alliance.

Taking traffic around the eastern side of the Peel-Harvey Estuary prior to joining the existing dual carriageway on Old Coast Road reduced the journey time from Perth to Bunbury.

In January 2014, it was described as "the busiest, most unserviced, long stretch of highway in the nation" by MP Murray Cowper, Member for Murray-Wellington.

The facilities, which consists of a national fuel retailer and food and beverage outlets along with other amenities located on both sides of the highway, were initially expected to be completed by the end of 2014,[76] but work was put on hold due to a legal dispute between the developer and landowner.

[needs update] The renaming was considered unusual, as it affected a significant length of a major road, which was the address of eleven residential properties.

Now at the eastern edge of the Leschenault Inlet, Old Coast Road enters Australind and travels along the shoreline for nine and a half kilometres (5.9 mi).