Coober Pedy, an opal mining town in South Australia, is located in an extremely inhospitable environment. Desert temperatures in the summer usually exceed 104 degrees Fahrenheit and it can get quite chilly in the winter. Years ago, the original miners stumbled upon a solution to living there: Build everything underground. They began using old opal mines or digging out new structures for housing. The underground homes naturally maintain a comfortable temperature. They require no air-conditioning or heating systems, greatly reducing the residents' carbon footprints. Most of the towns 1,916 residents continue to build and live underground.
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