As a kid, you were convinced that enough digging in the backyard would take you straight through to China. That exotic adventure never panned out, but at least one man never grew out of tireless tunneling—regardless of whether or not China really lay on the other side.

In 1902, deep in the Mojave Desert in California, a man named William Henry Schmidt began chiseling. Over the next 36 years, he would dig a 2,087-foot tunnel that led absolutely nowhere. Using hand tools and explosives, with only the help of two donkeys, the lonely miner forged a tunnel from one side of the Copper Mountain to a ledge on the other side.

Schmidt had arrived in California after his family had been wiped out by tuberculosis in his home state of Rhode Island. He too had apparently been struck with the disease and was told by a doctor that his only shot at survival was to move to a drier climate. So, Schmidt followed the gold rush to the El Paso mountains and claimed an area of mining land. Then, he set to work building a shortcut that would take the minable minerals he found through the mountain. The Mojave is rich with silver, tungsten, gold, and iron deposits. While he tunneled, he’d work summer side jobs at nearby ranches to support himself for the rest of the year. After the tunnel was complete, Schmidt went about building a rail line through it.