Slovenia’s Ancient Skocjan Caves are Mesmerizing

These formations are some of the largest subterranean chambers in the entire world

Visitors navigate the Cerkvenik Bridge. Source: Ramón
Interior chamber. Source: Archives Park Škocjanske Jame, Photo by: Borut Lozej, Bogdan Kladnik.
Reka River. Source: Archives Park Škocjanske Jame, Photo by: Borut Lozej, Bogdan Kladnik.
Source: Archives Park Škocjanske Jame, Photo by: Borut Lozej, Bogdan Kladnik.
Cerkvenik Bridge, 47 meters above the Reka River. Source: Archives Park Škocjanske Jame, Photo by: Borut Lozej, Bogdan Kladnik.
Light filtering through the cave. Source: Archives Park Škocjanske Jame, Photo by: Borut Lozej, Bogdan Kladnik.
Škocjan Cave entrance. Source: Wikipedia
Limestone pools. Source: Jure Zvan
The elephant stalagmite. Source: Ben Thé Man
Amazing formation within the Škocjan Caves. Source: Ramón
Large chamber. Source: Ben Thé Man
Cave exit. Source: Viajero Italico
A view of the Big and Small Valley in Škocjan—the entrance to the caves is located at the bottom of the two valleys. Source: Archives Park Škocjanske Jame, Photo by: Borut Lozej, Bogdan Kladnik.
Outside the caves. Source: Archives Park Škocjanske Jame, Photo by: Borut Lozej, Bogdan Kladnik.
Water through the Škocjan Caves. Source: Juanma Pérez Rabasco

Referred to as the "Underground Grand Canyon," the Škocjan Caves in Slovenia are considered some of the largest subterranean chambers in the world. Like many natural wonders, the caves were formed over vast periods of time by a river, the Reka, which still flows along the bottom of the underground canyon. Though the "Underground Grand Canyon" nickname is catchy, the Škocjan Caves probably have more in common with New Mexico's Carlsbad Caverns; the cave's largest canyon measures, at some points, almost 200 feet across and 460 feet tall and is spanned by a narrow, vertigo-inducing bridge. (The Grand Canyon, meanwhile, is 18 miles across at its widest point.) Thanks to the water flowing through the caves, a number of stunning geological features can be found inside the chambers, including limestone pools and massive stalagmite formations.

Archaeologists have found evidence that humans lived in the caves as early as 3,000 B.C. In one of the cave's chambers, explorers found a burial site, complete with 10 skeletons and funerary goods. The first written records of the caves date back to the second century B.C., and the caves are marked on one of the oldest published maps of that region of the world (what is now Slovenia). Modern exploration of the caves began in the late 1800s, and continues to this day.

The caves are also home to a very unique inhabitant: the blind cave salemander (Proteus anguinus), know as the človeška ribica (human fish) by locals because of its fleshy, pink skin and resemblance to a human embryo.

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Visitors wishing to reach the caves can go year-round—the chambers maintain a constant temperature of around 50 degrees Fahrenheit all year. The closest city to the caves is Divača, Slovenia, which is accessible via car or train.

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