Cavers heard wind roaring from beneath a rubble-choked pit in New Mexico; after years of digging they broke through in 1986, and more than 145 miles of Lechuguilla Cave have since been mapped

For decades, Lechuguilla Cave was just a footnote in New Mexico’s Guadalupe Mountains: a 90-foot entrance pit leading to 400 feet of dry, dead-end passages that had once been mined for bat guano. But in the 1950s, cavers began noticing something strange: wind roaring up from the rubble-choked floor, hinting at hidden passages below.

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