Photo: Josh Hydeman

American cavers were first to descend the 1,200-foot deep Sotano De Las Golondrinas, better known as the Cave of Swallows, in 1966. It’s one of the world’s largest cave shafts in the world and one of Mexico’s 13 natural wonders. The cave is so enticing that, in 2012, then President of Mexico, Felipe Calderon, was lowered by rope to the bottom of the shaft to experience it first-hand.

Today, there’s a paved road leading to the entrance of the cave to encourage tourism, and people from all over the world visit to peer over the edge and watch the white-collared swifts who call the cave home. Very few of these vistors actually rappel inside to see the bottom. Despite the popularity of this natural wonder, the inside of the cave is still a genuine wilderness experience. The limestone karst of the area of Acquismon is home to many caves, Sotano de Golondrinas being only one of them. Here is a collection of photographs from the Cave of Swallows and other shafts surrounding it.

Photo: Scott Christenson and Jerry Cindric ascend out of Sotano De Huasteca, a 420-foot deep limestone pit in Aquismon. Using mechanical ascenders to climb the rope, they are able to quickly and efficiently exit the cave. Rock climbing the walls in the cave would disrupt the nests and habitat of the white-collared swifts. Leaving behind climbing chalk and climbing bolts would be unnecessary to explore the cave and is damaging to the fragile ecosystem.