WESTONARIA, South Africa (AP) — For those who grumble about their daily commute, imagine this ride to work: clamber into an elevator cage and plummet 2.4 kilometers (1.5 miles) into the earth, so fast that ears pop from the changing air pressure. Then board a small railroad car that creaks and grinds the same distance to the outer reaches of a South African gold mine.

It gets humid down below. Sweat flows. For the unaccustomed, the din of drills and other machinery is disorienting. Travelers are weighed down by boots and a jumpsuit, a helmet with a mounted flashlight and a “self-rescuer,” a metal canister with a breathing tube and an oxygen supply in case something goes wrong.