It’s a predictably sunny day in the Chihuahuan Desert of southern New Mexico and the cottonwood trees lining the Tularosa Creek glow copper in midmorning rays. I relish their rare shade on a walk downstream to a small wooden bridge, to the far side of the Tularosa Canyon. I then bat away prickly mesquites and creosotes that poke at my shins on the hike over to a round, semi-subterranean ceremonial structure known as a great kiva. It’s still partially buried in the arid earth, so I fall to my knees, grab my trowel, and begin the meditative work of unearthing this ancient structure—one tiny scrape at a time.

Some folks know this prickly patch of land, three hours south of Albuquerque, as the place that turned Henry McCarty into Billy the Kid; others associate it with nearby Roswell and its fabled UFOs. David Greenwald, president of the Jornada Research Institute, a nonprofit that studies the archaeological heritage of New Mexico, sees what everyone else seems to miss. He’s dedicated his life to uncovering the hidden cities built more than a millennium ago by an advanced society that transformed this lifeless desert into vast fields of corn, beans, and squash… (continue reading at AFAR).