A journey into the caverns of Actun Tunichil Muknal is a journey to the entrance of Xibalba—the Mayan underworld. To get there you’ll need to endure a bumpy 45-minute drive, a 45-minute hike through the jungle, three river crossings on foot, and a claustrophobia-inducing swim into the narrow mouth of the waterlogged cave. But at least you’ll make it out alive.
During the late Classic period of the civilization (700 to 900 A.D.), Maya came to the cave to perform sacrificial rituals, believing it to be a gateway to Xibalba. Carrying flaming torches, burning incense, and holding ceramic pots containing edible offerings, they led people inside to be killed and offered to the gods.
Archaeologist Thomas Miller discovered Actun Tunichil Muknal, also known as ATM, in 1986. Excavations over the next decade uncovered the bones of 14 people, including six children under the age of 3, in a large chamber called the Cathedral. Cranial trauma and the positioning of the remains indicated they were fatally struck on the head and thrown to the ground. Left undisturbed in the dripping cave for approximately 1,200 years, the bones are coated in calcite crystals, giving them a sparkling, puffy appearance. Surrounding the human remains are hundreds of pieces of broken pottery—following sacrificial ceremonies, the Maya would smash the ceramic pots to release the energy contained within.
A full skeleton, lying on its back and seeming to have its head raised to look at you, stands out among the scattered bones. Calcification has softened its harsh contours, and the crystals dusting the bones glitter in the light of your headlamp. This is the Crystal Maiden. She died at 18—probably in a particularly violent way, judging by her two crushed vertebrae.