A building in El Paso, Texas is the site of a century-old mystery. On the side of the building: a mural of a turtle. In the basement: a network of walled-off tunnels.
Larry Potash journeys to the Mexican border to unearth the mysteries of the Turtle Tunnels underneath the streets of El Paso. What purpose did they once serve? And what can they tell us about America’s past?
This is the backstory.