Coober Pedy is a town in northern South Australia, 846 km (526 mi) north of Adelaide on the Stuart Highway. The town is sometimes referred to as the "opal capital of the world" because of the quantity of precious opals that are mined there. A blower truck is raised above the town sign, representing the importance of opal mining to the town's history. Coober Pedy is also renowned for its below-ground dwellings, called "dugouts", which are built in this fashion due to the scorching daytime heat.