This is Curt Bowen, explorer, cave diver, climber and publisher of Advanced Diver Magazine climbing into a cenote in Yucatan, Mexico. While this cenote is clearly not virgin, that 'ladder' is actually the tracks from a narrow gauge railroad. These tracks are common sights in Yucatan, where they were used by plantations and haciendas to move goods around town. Often in the rope making business, these haciendas were the economic engine in an area. They did employ slave or indentured labor.