Highway 1 continues around the rest of Australia, joining all mainland state capitals, and connecting major centres in Tasmania.

Highway 1 is often associated with summer road excursions for people of New South Wales since the whole route passes very near to the ocean.

The route was compiled from an existing network of state and local roads and tracks.

In 1974, the Sydney-Newcastle Freeway section was declared part of the National Highway, and the route marker was subsequently updated to National Highway 1 for this section[3] In 1993, the route numbering was further complicated with the introduction of the Metroad numbering system within the Sydney metro area.

In 2013, alphanumeric route numbering was introduced to New South Wales, and all sections of Highway 1 were changed to carry either the M1 or A1 designation, depending on the grade of the road.