The Princes Highway starts from Sydney in New South Wales and runs almost parallel with the coast for 2227 kilometres to Port Augusta in South Australia.

The New South Wales section runs south from Sydney to just south of Timbillica. It is 530 kilometres long and a 7.15 hour drive.

The Victoria section runs in a south-westerly direction from just south of Timbillica, through Melbourne, to just east of Mount Gambier. It is 935 kilometres long and a 10.40 hour drive

The South Australian section runs north from just east of Mount Gambier to Port Augusta. It is 762 kilometres long and an 8 hour drive. Sections of the highway (B1 and A1) are also known as South Eastern Freeway, Port Wakefield Way and Augusta Highway.