Current Jewel Cave Statistics:
Length: 200.33 miles / 322.40 km (as of December 19, 2018)
Depth: 832.1 feet (Jewel Cave is the deepest cave in the Black Hills.)
Largest Room: The Big Duh. 570 feet long, averages 90-180 feet wide and 30 feet high.
Tallest Passage: Wall Street. 136 feet.
Why explore Jewel Cave?
The physical and mental challenges of cave exploration address a deep-seated human desire to venture beyond the known into the frontier. Exploring cave passages where no one has ever been before is certainly exciting, and it also provides information essential for managing both cave and surface resources. For this reason cave explorers must meticulously survey each passage that they find, and create a detailed map.
Who explores the cave?
Cave exploration and mapping is done entirely by volunteers. Those wishing to participate in the exploration of Jewel Cave must have prior caving experience, possess a strong cave conservation ethic, be able to fit through tight spaces, and have the endurance for long caving trips. All trips are led by qualified trip leaders who have been approved by the Monument's cave resource management staff.
How far does the cave extend?
Jewel Cave is under about four square miles of surface area. More than 55% of the known cave is outside the Monument boundaries, under the Black Hills National Forest.
How long is the cave?
At more than 200 miles in length, Jewel Cave is currently the third longest cave in the world. Airflow studies indicate that there is a lot of cave yet to be discovered.
What is the depth of the cave?
The elevation range of Jewel Cave spans 832 feet. This is its official "depth." The highest point in the cave is 5,410 feet above sea level, and the lowest point is at 4,578 feet.
The cave's depth below the surface varies greatly, due to the thickness of overlying rock layers and characteristics of the surface topography. The cave intersects the surface in Hell Canyon, at the only natural entrance. The deepest point in the cave is 749 feet below the surface.
Where is most exploration taking place?
Several recent exploration trips have focused on the western branch of the cave, where there are many "leads" (unexplored passages) with strong airflow. Airflow within the cave is the single best indicator that large areas of the cave are yet to be discovered. In 2014, explorers found a narrow fissure with airflow in the western branch that they called the Southwest Splinter. This narrow fissure has since led to the discovery of over 24 miles of new passages, and the first lakes discovered in Jewel Cave. There is still no end in sight! Recent expeditions to this area have returned to the surface with over a mile of newly discovered passages, on average, per trip.
How long does it take to reach the "end" of the cave?
It currently takes over 12 hours one-way to reach the end of the southwestern portion of the cave. Due to the distance that must be traveled and time involved to reach this location, a new camp was established in December of 2016. This camp became known as Deep Camp, and is the third camp established in the cave. It takes approximately 8 hours to reach Deep Camp from the elevators, and from there, explorers travel to the end of the cave to continue mapping. As they find new passages; the end of the cave gets farther away, and it becomes more difficult to explore. Currently, cave explorers will spend up to four days underground to maximize their safety and productivity at the end of the cave.