Where is it? Brewarrina Fish Traps, on the banks of the Barwon River in north-west NSW
Forty-thousand years is a long time to be sitting in the same riverbed, but the engineering prowess of early indigenous Australians is evident from the Brewarrina Fish Traps, a system of stone weirs and pools that are still intact all these years later. The fish traps are about half a kilometre long and were devised to catch fish as they swam upstream. Pretty cool stuff.