freeway proper, as it is not built to full freeway standards, containing left-in/left-out intersections and the at-grade intersection at the foot of Mount Ousley, where the motorway proper diverges from Mount Ousley Road. This intersection is proposed to be replaced by a grade-separated interchange. The federal government announced funding for the interchange in May 2021. In November 2015, it was announced that the section between Bulli Tops and Picton Road would have a third lane added in each direction. , detailed design works have been completed. Gwynneville to Yallah section The construction of the first stage of the Princes Motorway between Gwynneville and Yallah commenced in May 1959. This was the length from the interchange of the Princes Motorway and Memorial Drive in Gwynneville to the Princes Highway at West Wollongong. This forms the majority of what was built as a north-south bypass of Wollongong central business district, and was the first section built of an arterial road planned to run from Thirroul in the north to Dapto in the south. The CBD bypass was opened from the Princes Highway at North Wollongong to Foley Street in December 1959, from Foley Street to Phillips Avenue in 1961 and from Phillips Avenue to the Princes Highway at West Wollongong in July 1963. Duplication from Gwynneville to West Wollongong was completed in 1965. In March 1964 the connector from Mount Ousley Road at the foot of Mount Ousley to the CBD bypass in Gwynneville was opened as a single carriageway, and was duplicated in the early 1970s. The intersection with the CBD bypass at Gwynneville remained an at-grade intersection until the grade-separated interchange entered service in December 1998. Following completion of the Mount Ousley-Gwynneville connector the freeway continued making its way southward, with the extension from West Wollongong to The Avenue at Figtree opening in 1967, and then from Five Islands Road to Northcliffe Drive in 1973 (albeit as a single carriageway, with duplication finished in 1975). The intermediate section from The Avenue to Five Islands Road, including the interchange with Masters Road, was opened in 1975. Construction then continued south from Northcliffe Drive to Kanahooka Road in 1978 (with duplication concluding in 1979), to Fowlers Road in 1981 (with duplication concluding in 1983), to the Princes Highway near Tallawarra power station in 1986 (with duplication concluding in 1987), and to Yallah (in conjunction with grade separation of the junction with the