List of road routes in South Australia
Roads routes in South Australia comprise both National Highways and state routes. All routes are alphanumeric, with the first letter denoting the standard or function of the road.
Since 1955 South Australia had major rural roads numbered as part of national routes and Highways. In 1998/1999 South Australia introduced "Trailblazers" with A, B and M route numbers in the Metropolitan area and tourist areas of Victor Harbour and the Barossa Valley. This system was extended to cover country areas starting in 1999/2000
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