07-Oct-2014 -- On our last extended visit to Australia in 2002, we successfully visited the confluence 29S 142E and wanted to repeat this on our current trip 12 years later.
Driving a Bushcamper from Alice Springs to Mount Isa via the Sandover Hwy, the confluence 21S 138E was just 4 km off the road on the state border between the Northern Territory and Queensland.
We followed the state fence track 4 km south and literally drove over the confluence with no problems at all. The confluence lies in the often-cited middle of nowhere. It's a flat area with hardly a shrub.