It's not that fantastical, it's resembles a small town and has aboveground buildings as well. The underground dwellings are mostly rented to tourists nowadays.
Few things I remember from there around ~10 years ago:
Coober Pedy literally means 'White Man's Warrens' in Aborogeni.
You have yo register your ID to buy alcohol and are limited to 2 beers/1 spirit per day because the aborogenies keep getting tourists to buy them hooch.
The 1st part pf the Vin Disel Riddick Epic 'Pitch Black' was filmed there and the full size spaceship prop is still in place.
A hardcore leftist reposting a tweet with the user/source mysteriously cropped out? 'yall a bunch of deramged, crybaby tards.