Coober Pedy is called - no, Coober Pedy is - the opal capital of the world.
It's not the only opal mining town in Australia, but it is by far the biggest and produces more opal than any other place in the world.
You know you are getting closer to Coober Pedy when the South Australian Outback left and right of the Stuart Highway turns totally flat, barren and featureless.