In New South Wales, Highway 1 is a 1,351-kilometre (839 mi) long route that crosses the state, from the Queensland/New South Wales border near Tweed Heads to the Victorian border near Timbillica. It provides the main coastal route between Brisbane and Melbourne via Sydney. Highway 1 continues around the rest of Australia, joining all mainland state capitals, and connecting major centres in Tasmania.

Australia's Highway 1 is a network of highways that circumnavigate the country, joining all mainland capital cities except the national capital of Canberra. At a total length of approximately 14,500 km (9,000 mi) it is the longest national highway in the world, surpassing the Trans-Siberian Highway and the Trans-Canada Highway. Over a million people traverse some part of the highway network every day. It is the longest continuing highway in the world as the Pan-American Highway is separated by the Darién Gap and AH1 is separated by the Sea of Japan.