Wine production near the coast (famous is Barossa Valley), the beautiful Flinders Ranges and outback towns such as Coober Pedy, home of the Opals. Also some of the most famous caves of Australia.
South Australia has several karst areas, including the biggest and most interesting area in the Nullabor plains, a desert region. Unfortunately this area is not developed and thus inaccessible to the normal tourist.
The Mt. Gambier karst area is the opposite to the Nullabor plains, as it is located inside (or below) a town and very well developed. It is rather small but very interesting. Beneath the caves and sinkholes, there is a maar with a blue lake inside.