In the far north of South Australia sits Coober Pedy, a town with over 250,000 unmarked mine shafts, a golf course with no grass, and a population that lives underground to escape scorching heat that has hit 119 degrees Fahrenheit. This episode explores how an unforgiving desert created one of the most culturally unique towns on the planet, beginning with an accidental opal discovery by a 14-year-old boy in 1915 that made it the opal capital of the world.

The town’s growth was shaped by returning World War I soldiers who brought trench-digging skills, a postwar wave of European immigrants, and Aboriginal miners who entered the industry from the 1940s and once revitalized a dying town. A 165-square-foot claim limit democratized the wealth and created a pockmarked human ant farm. Residents carve comfortable dugout homes into stable sandstone, where thermal mass keeps temperatures at a constant 23 degrees Celsius year-round.

• The desert geology and the meaning of the town’s name, white man’s hole
• Why Aboriginal people knew of the opals but valued quartz tools instead
• The 17,000-carat Olympic Australis and why only 5 percent of opals are precious
• How dugout homes use thermal mass to replace air conditioning
• The grassless nocturnal golf course with reciprocal rights at St. Andrews