The Dukes Highway is a 189 kilometre highway corridor in South Australia which links the Australian cities of Adelaide and Melbourne. It is part of the National Highway system spanning Australia, and is signed as National Highway A8. The Dukes Highway starts in Tailem Bend on the Princes Highway and extends southeast to the state border near Bordertown, South Australia. The highway continues in Victoria as the Western Highway, with the same route signage (National A8).