Métlaoui exists because of the open-cast and underground phosphate mines that surround the town, opened by French engineers in 1899 and still the lifeline of the local economy. Tunisia remains one of the largest phosphate producers in the world, and the rusted conveyors, slag heaps, and rail sidings around the town are part of the landscape.
The mines are not open to visitors, but the industrial scenery between Métlaoui and Redeyef is striking in its own right, especially from the Lézard Rouge train. The town's small museum has occasional displays on mining history.