Not really a street circuit as such or an original design, this circuit hosted the Australian Grand Prix in 1939 around the town of Lobethal in the Adelaide Hills.
http://www.gmap-pedometer.com/?r=4486861
An onboard lap of the circuit: http://www.youtube.com/watch?v=mQZqAVvfsJk
At 14km long its the longest circuit ever used in Australia. I think it would be better suited towards an endurance race although realistically it would never happen.
One can dream though :P