A total of 109 monoliths have been excavated at El Infiernito: 54 in the northern row and 55 in the southern, aligned on an east-west axis across the Monquira Valley on the Altiplano Cundiboyacense. The lithic pieces are carved from pink sandstone, many shaped into columns with an incised ring. Archaeoastronomer Juan Morales studied the alignments in detail and found that the main columns point at an azimuth of 91 degrees toward the summit of Morro Negro hill -- precisely where the sun rises during the equinox. On the summer solstice, the sun rises above sacred Lake Iguaque when viewed from the columns, connecting the observatory to the Muisca creation story. The arrangement apparently represents the Muisca calendar, dividing the site into two sacred fields: Infiernito No. 1 to the north and Infiernito No. 2 to the south.

El Infiernito was more than a timekeeping device. The site served as a center for religious ceremonies and spiritual purification rites, a place where the Muisca gathered to worship the sun and encourage fertility of both land and people. Several earthworks surround the standing stones, and burial mounds dot the area, suggesting the site held significance across generations. The Muisca people -- sometimes called "The Salt People" for their halite mining -- inhabited the Altiplano Cundiboyacense before the Spanish conquest. Their society was organized under caciques and priests, with the zaque based in nearby Hunza (modern Tunja) governing the northern territories. El Infiernito was part of a broader sacred geography that included Lake Iguaque, where the goddess Bachue was said to have emerged with the first child of humanity.

The first formal description of the site came in 1847, when Colombian army geographer Joaquin Acosta reported 25 stone columns half-buried in the valley. Alexander von Humboldt studied the findings and recognized that the stone alignments could anticipate astronomical phenomena -- solstices and equinoxes -- based on their orientation relative to the sun and moon. But it took another century and a half before the site received proper archaeological attention. Anthropologist Eliecer Silva Celis led the first formal excavations in 1981, uncovering far more monoliths than Acosta had found and establishing El Infiernito as an official archaeological park. Other lithic monuments from the Muisca culture survive at Sutamarchan, Tunja, Ramiriqui, Tibana, and Paz de Rio, but none match El Infiernito's scale or astronomical precision.

The Spanish saw diabolism where there was science. They condemned the phallic forms as obscene and labeled the site a place of pagan worship, a judgment that gave El Infiernito its enduring name. But the stones tell a different story -- one of a people who observed the sky with enough care to track the solar year, who marked the equinoxes by sighting over hilltops, and who wove astronomy into their spiritual life so thoroughly that the act of measuring time was itself a religious practice. Today the site sits quietly in the countryside outside Villa de Leyva, the pink sandstone columns standing in their rows as they have for centuries, still pointing toward the same sunrise they were built to mark.