Residents of a small Australian town called Coober Pedy famous throughout the world because of its unusual life. Residents of this town live deep in the underground, far away from civilization. In order to live in a place where dust storms occur constantly, and daytime temperatures can rise to 50 degrees Celsius in the shade, Coober Pedy residents began to build underground dwellings. But why did they live here, you ask? Opals. Coober Pedy is the largest opal mine in the world.