Professional Adventurer George Kourounis knew he needed to visit  the Cave of the Crystals, located nearly a 1000 feet beneath northern Mexico, the moment he saw a photograph from inside the cave.READ MORE IN THE ATLAS: <a href="https://www.atlasobscura.com/places/giant-crystals-naica" target="_blank">https://www.atlasobscura.com/places/giant-crystals-naica</a>

The Great Stalacpipe Organ (Classic)

An audio guide to the world’s strange, incredible, and wondrous places. Co-founder Dylan Thuras and a neighborhood of Atlas Obscura reporters explore a new wonder every day, Monday through Thursday. In under 15 minutes, they’ll take you to an incredible place, and along the way, you’ll meet some fascinating people and hear their stories. Our theme and end credit music is composed by Sam Tyndall.