Cave Explorers

Past and Present Jewel Cave Explorers

Dwight Deal

In 1959, Dwight Deal, a graduate student from Rensselaer Polytechnic Institute in New York, came to the Black Hills. Fresh out of college, Dwight had taken a job with an oil company in nearby Wyoming. He was an active member of the National Speleological Society, and had plenty of enthusiasm and scientific knowledge to fuel his desire to explore caves. Dwight's job allowed him weekends free to devote to cave exploration, and he had become aware of Jewel Cave through a group of cavers from Colorado who had been surveying nearby Wind Cave. He joined them one weekend for a special trip into Jewel Cave, then approached the National Park Service about getting permission to continue surveying there. He was granted a Special Use Permit, but was told that in order to use it in Jewel Cave, he would have to have at least two other people go with him. Dwight had become acquainted with Herb and Jan Conn when they were all still living in the East, and knew they were now in the Black Hills. He persuaded the Conns to join him. On the first few trips, Dwight instructed Herb and Jan in the art of surveying the cave while exploring its passageways. By the spring of 1961, Dwight had moved away from the Black Hills, but not before over 5 miles (8 km) of cave had been mapped. He returned in the summer of 1961 to work on a master's thesis on the geology of Jewel Cave for the University of Wyoming. In May of 1962, Dwight Deal did an inspection tour of the proposed new cave tour route. It was a 4-hour trip to the "Formation Room", but he was so impressed by the beauty of the dripstone deposits on top of the crystals that he recommended in writing to the park superintendent that an effort be made to provide public access to this area. His efforts are rewarded with each tour group that enters that room on the Scenic Tour and gasps in delight at this impressive stop on the route.

Herb & Jan Conn

At the Historic Entrance Herb and Jan Conn began a lifelong connection to the Black Hills of South Dakota in 1946. Both were born and raised on the East Coast, and during WWII, Herb worked as an electrical engineer for the Navy Department in Washington, DC. Although this adventurous young couple had first been exposed to cave exploration in West Virginia, their real love at that time was rock climbing, a hobby they had developed on the cliffs of the Potomac. In 1946 they decided to leave the Washington, DC area and head west to practice rock-climbing full time. Over the next few years the Conns traveled extensively, working wherever and whenever they needed to to support their climbing. They worked in resorts, factories, for a furniture manufacturer, and for a venetian blind company. They originally planned to settle in Colorado, where they knew the mountain climbing opportunities were abundant. But 1949 found them in the Black Hills of South Dakota, where they were convinced that western South Dakota’s great weather would give them an opportunity to spend more days mountain climbing. They bought 20 acres of land four miles from Custer and settled in. One of Jan's earliest significant climbing feats in this area was her accomplishment of being the first woman to free-climb Devils Tower. In 1959, geologist and caver Dwight Deal had done some exploration in a small, but pretty cave called Jewel Cave. He needed some companions who might help him continue his exploration trips there and turned to his friends, Herb and Jan. He asked if they would be interested in grubbing around underground and, after thinking it over, they replied they would try it "once". That one trip turned into a passion of exploring Jewel Cave that lasted for over 20 years. What actually seduced the Conns into continuing their caving trips in Jewel Cave was the challenge of surveying: measuring and sketching the convoluted passageways of this twisting, turning cave captured and held their attention. From 1959 to 1979, Herb and Jan mapped 62.36 miles of the interior of Jewel Cave. The Conns discovered what is now the Scenic Cave Tour route in 1961. The National Park Service was intrigued by their reports of high, narrow passageways, huge rooms and unusual speleothems (cave decorations). The Conns suggested that the part of the cave they had been surveying might prove perfect for development of a new tour route. In addition to assisting with the construction of this trail, Herb also designed the lighting system and dramatic placement of lights still in use today. The cave winds that enticed the explorers further into the cave fascinated Herb, and in 1966 he produced an important scientific report explaining reasons for these barometric winds. The Conn's book, "The Jewel Cave Adventure" serves not only as a record of their years of cave exploration here, but as an exciting tale of adventure even for non-cavers. As for their public service in the development of a great national monument, they are inclined to shrug that off, too. "If people do what they really want to do, "says Jan, "then they will eventually contribute something to the world."

Current Cave Explorers

While Herb and Jan Conn were still actively exploring and mapping Jewel Cave in the late 1970s, a graduate student from South Dakota School of Mines and Technology, Mike Wiles began accompanying them on caving trips. In 1979, Mike began a career with the National Park Service, first as a Volunteer-in-Parks, then as a seasonal park ranger. In 1980, he began an apprenticeship of sorts with the Conns. This sharpened his caving skills, heightened his awareness of cave ecology, and introduced him to the world of underground surveying and mapping. By mid-1981, the Conns had effectively retired from exploring Jewel Cave, leaving Mike to take the lead in ensuring continuing exploration. Over the years, Mike has organized exploration, survey and mapping of Jewel Cave by teams of interested and qualified cavers from throughout the U.S. Today, as Cave Management Specialist at Jewel Cave National Monument, Mike is responsible for compiling all the information gleaned from caving trips to effectively manage and preserve the cave.

Notes from a Jewel Cave Explorer

by Andy Armstrong

Exploring Jewel Cave is different from caving in other parts of the United States. Many factors make Jewel Cave unique: its great length, strong airflow, and difficulty of travel all contribute to a style of caving that I have not experienced elsewhere.

As of early 2006, Jewel Cave has been surveyed to a length of 135 miles, and is the second longest cave in the world. The longest is Mammoth Cave in Kentucky at 367 miles. One primary difference between the two caves is the number of entrances. The Mammoth Cave System has more than 25 entrances and has been explored and interconnected between these many points of access. Jewel Cave has only two entrances about a mile apart from one another. One of these is an artificial elevator entrance. This not only makes Jewel the longest cave in the world with only one natural entrance, but also means that a lot of distance must be traveled to reach the edges of the known cave. In the east, the “end” of the cave is seven miles from the elevator, about eight miles from the Historic Entrance. It would be very difficult to travel this route both directions in one day. So, most exploration out there takes place as four-day camp trips. Camping in the cave was begun in 1997 when a camp was established in the Big Duh, about five miles from the elevator. Since that time about 22 miles have been surveyed, and the known end of the cave is 3.5 hours from camp. On the most recent camp trip, we estimated that we traveled about 20 miles underground in four days. Such distances are unheard of except in a few other caves worldwide. Seven miles in is probably the farthest underground distance you can travel from a cave entrance in the United States. At the edge of the known cave there are unexplored leads and strong airflow, indicating still more cave beyond.

Another unique thing about Jewel is that there is strong airflow deep in the cave. I have explored other caves with strong barometric wind, like Wind Cave and Lechuguilla Cave. Both of these caves have extremely strong winds at the entrance, but inside, the airflow disperses through many passages and can hardly be felt. In Jewel Cave, there are definite airflow routes. When traveling through the Miseries or the Tenderizers, the airflow can be quite intense. There are places named Hurricane Corner, the Exhaust Pipe, Snow Blower, Long Winded Passage, and the Mind Blower; all because of the wind blowing through these passages. There are even places where the wind is so strong that it is audible. Thus, we get places called the Humdinger, the Horn, and the Whistle Stop. When exploring a cave, airflow is probably the best indication of more cave beyond. So we follow the wind to see where the cave will go. Barometric airflow can be used to calculate the cave’s volume. Herb Conn did volume calculations based on airflow and came up with four to five billion cubic feet. The known cave only accounts for about 100 million cubic feet. This means there could be more than 95% of the cave still awaiting discovery.

Jewel can be a difficult cave to explore. It is not particularly dangerous among caves of the world; for example, there is no vertical caving involved and there is virtually no chance of flooding. However, the distances covered and the seemingly endless succession of obstacles can make for some hard, tiring trips. Heading east from the elevator, one of the first major obstacles is the Miseries. The Miseries is a series of crawls about 1,800 feet long. There are 1,100 feet of Miseries proper, followed by 700 feet of Mini-Miseries. The Mini-Miseries include 200 feet of belly-crawls, and tight spots like the Calorie Counter and the Funny Little Hole. After the Miseries, there are miles of travel over breakdown boulders, up and down ladders, and free climbs of varying difficulty. The ever-present “manganese” (manganese oxides and hydroxides) coat the trail surfaces making the footing slippery. There are also long stretches of walking, which can be covered at a brisk pace. On the way out of the cave, some cavers actually look forward to the Miseries, because they can lie down as they crawl and rest their feet. On the way out to camp there are designated rest stops about each hour along the way. The cavers take short breaks at each of these places. It is necessary to eat a snack at each stop in order to maintain energy levels for the long trip. Traveling in this way, the camp can be reached in about 8 hours.

So, exploring at Jewel is rather unique. Caving here can be strenuous and committing. Even experienced cavers that are new to Jewel need to go on a few “break-in” trips before heading far out beyond the Miseries. Why go to all the trouble? Because leads abound, and the recently discovered passages are not small. Some of the biggest rooms in the cave are at the far eastern end. Jewel Cave is still “going”. In 2005, 4.3 miles of new passages were discovered and mapped. Jewel Cave remains one of the most promising underground frontiers in the United States.

Last updated: April 10, 2015

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