Wind Cave National Park

IMG 8624The discovery and reports of incredible beauty in regions of the United States by early surveyors caught the attention of national leaders who quickly decided these areas should be set aside and shared by all Americans. Congress acted quickly and established Yellowstone as the nation’s first national park on March 1, 1872. Mackinac National Park was designated in 1875, but later withdrawn in 1895. In 1890, Yosemite, Sequoia, and General Grant (King’s Canyon) were also declared national parks largely due to reports from surveyors of the U. S. Geological Survey who were performing quad sheet mapping. Mount Rainier was designated in 1899 and Crater Lake followed in 1902.

The eighth national park, however, was designated for what lies below the surface and not above. Wind Cave is located in the southern Black Hills region of southwestern South Dakota eight miles north of Hot Springs. While a large assortment of wildlife including bison, elk, deer, and prairie dogs roam the grasslands mixed with Ponderosa pine on the surface, many miles of passageways lie hidden from view below the surface with its true extent yet to be determined. The cave was immediately deemed unique because it contains calcite formations known as boxwork that are rarely found elsewhere and the length was advertised as being 97 miles. Wind Cave is the world’s sixth longest cave and was the first to become designated a national park anywhere that protects a subterranean resource.


The original above ground boundary of the Wind Cave National Park, as established in 1903, is outlined in blue. Although part of the western boundary has been relinquished, the park has greatly expanded to the north and east to now comprise of 33,924 acres in 64 different sections.

The discovery of the cave dates back to American Indians thousands of years ago. It is held sacred by many tribes; the Lakota consider it their origin site. Europeans found the cave in 1881 when brothers Tom and Jesse Bingham heard wind rushing out from a hole in the ground and began to investigate. Less than a decade earlier, the Custer Expedition of 1874 verified rumors of gold in the Black Hills, prompting the area to quickly become populated with white prospectors and settlers. Commercialization of the cave began almost immediately and by the end of the first decade, the exorbitant sum of $1.00 was being charged to anyone wishing to venture inside.

Surveys on the surface by the General Land Office came to the Wind Cave area in September and October of 1892—a decade after its discovery, prompting intense legal disputes over who had title to the property. By the late 1890s, the GLO was consumed with examining all area claims in an attempt to sort out true ownership. Several claimants were already selling specimens from the cave which prompted a drawn-out legal battle.

In 1899, the GLO decided to deny both mineral and homestead claims to the Wind Cave property, ruling that no claimant was entitled to it. It was further recommended the government hold the cave in reserve as a ‘public resort,’ thus removing it from any future private ownership and exploitation. The following year, all of Section 1 and a portion of the NE ¼ of Section 2, T6S, R5E, BHM surrounding Wind Cave were withdrawn from public settlement. The government was far from finished. Additional land withdrawals surrounding Wind Cave were made by the GLO in July 1901 and April 1902.


The establishment of Wind Cave as a tourist destination developed soon after its discovery. The staircase in this early image leads down to a small structure where the cave opening was located.

The decision by the government to remove land was initially claimed to be temporary “pending final determination of the question of the advisability of recommending the setting of said lands apart as a National Park for the purpose of preserving the beauties of the natural curiosities of the Wind Cave.” In defiance, at least one family continued to reside on the property into 1901. Twenty-one structures associated with early settlers where depicted on the GLO plats within the area where the government was eyeing a much-expanded reserve.

Explorers and visitors to the cave frequently carved or smoked their names into the walls and ceilings. In one room, subsequently known as the Post Office, visitors left signed calling cards. The unapproved entry into the cave prompted GLO Special Agent Michael A. Meyendorff to authorize a survey to determine the condition and extent of the cave prior to consideration as a national park. Chosen to perform the survey in April of 1902 was Myron Willsie, a civil engineer and U. S. deputy mineral surveyor based in Rapid City. Willsie utilized a sea-level bench mark near the entrance of the cave that had been carried by leveling from nearby lines established by USGS in 1899 on the Deadwood Datum.


Boundary Post No. 30 was one of just thirty-one specially-made survey monuments for the Wind Cave National Park boundary. This iron post was placed next to the stone monument at the SW Corner of Sec. 34, T5S, R5E, BHM.

Three main traverses were run inside the cave by noting the compass bearing, distance, and elevation at each traverse station. The main traverse consisted of 92 stations, followed by 21, and 11 stations for the other two. At each station, the width and height of the cave was also noted along with other pertinent remarks. Because the surveyors refused to open entrances generally too small to pass through, their entire survey of all lines was only 4509 feet. In his letter accompanying his notes and plat, Willsie stated the survey was slow and tedious due to the many short measurements within narrow and low places. Small crevices branching away from the main courses had indications of previously having been crawled through where it appeared many tons of specimens had been removed. Willsie also noted the danger of mapping inside a cave by reciting a story about a man becoming disoriented inside Wind Cave and wandering for over 60 hours before finding his way out.

USE DSCN8974On January 9, 1903, President Theodore Roosevelt signed into law legislation creating Wind Cave National Park which now comprised over 16 square miles. The need to mark the boundary above ground was forthcoming since fencing would eventually be required and to alert adjacent landowners where not to trespass.

Selected to survey the park’s boundary for the GLO was William H. “Billy” Thorn, a seasoned 43-year-old surveyor who was well familiar with the Black Hills. As an employee of the U. S. Geological Survey, Thorn had already established the boundary around the entire Black Hills National Forest in 1899. His other accomplishments in this region were placing the initial point for the Black Hills Meridian and establishing many township lines throughout the Black Hills. Despite being mainly known as a topographical mapping agency, the U. S. Geological Survey produced some of the nation’s most competent boundary surveyors of that era. Thorn’s instructions for surveying the Wind Cave National Park boundary were issued on July 10, 1906.


In a remote area away from roads, Boundary Post No. 28 was placed next to the N 1/4 Corner of Section 4, T6S, R5E, BHM. It has now endured through 115 years of extreme weather and forest fires.

On October 24, 1906, Thorn tested his light mountain transit at the Rapid City astronomical station that USGS had established in 1890 in preparation for the first triangulation network in the Black Hills. Three days later, Thorn arrived at Wind Cave and began his survey at the NW Corner of Section 34, T5S, R5E, and proceeded east. Each mile was first run random to find the government corners that had been established within parts of the four townships that the national park crossed into. At the beginning point, designated “Boundary Post No. 1”, a wrought iron pipe 4 feet in length and 3 ½” outside diameter with a flanged bottom and a brass cap was placed. The brass caps had slanted outer rims to provide an additional surface for information and were manufactured specifically for this survey marked “WIND CAVE NATIONAL PARK—U. S. FOREST RES.—No.—1906”. These large pipes would be used throughout the survey.

Glo 34 5 5

While some boundary posts were placed next to the GLO stone section corners, others such as No. 2, 3, 29 and 31 shown here, were placed adjacent to the wagon roads.

As the survey progressed, each GLO stone section corner was recovered and remonumented. The perimeter of the Wind Cave boundary was 17 miles and enclosed all or parts of 18 sections. Thirty-one boundary posts were placed along the perimeter making it perhaps one of the smallest boundary surveys of that era where brass caps were specifically embossed for only that survey. To ensure the public knew where the national park was located, boundary posts were placed adjacent to thirteen road crossings, which at that time were wagon trails. Two boundary posts were placed for section corners where the GLO corners were lost, while six posts were placed beside the recovered government stones. Hash marks were added on the outer rim with a chisel to denote the location of the monument within the township. Thorn placed seven of the iron posts 6 links (3.96’) from the true GLO stone section corner monuments. These caps were stamped with the corresponding section numbers and also with the letters “WC” to denote them as Witness Corners. However, those monuments placed directly beside the stones were not designated as witness corners. Invariably, surveyors in subsequent years have used the iron boundary posts beside and near the original GLO stones as if they marked the true positions. Thorn’s survey continued for eleven days and ended on November 6, 1906.


Without the natural beauty of the hidden formations below the surface, the Wind Cave National Park above the surface would have never been established.

In 1912, an additional 4,160 acres was acquired for game preserve purposes and buffalo were introduced. This attached area was given its own identity and designated the “Wind Cave National Game Preserve”. To encompass several nearby natural springs and to secure right-of-way for a water supply, additional land was purchased in 1931. The area where the game preserve was secured in 1912 was added to the national park in 1935, and additional land was acquired in 1946 to bring the total acreage to over 28,000 acres. To prevent the possibility of unsightly residential development, 232 acres were secured near the south entrance to the park and added in 1978.

Each time additional land was added to Wind Cave National Park, it required congressional approval. A bill brought before Congress in 2005 requested the purchase of 5,556 acres to encompass a four thousand-year-old buffalo jump and also land that could potentially contain endangered species such as the bald eagle, peregrine falcon, black-footed ferret, and American burying beetle. The largest obstacle to this purchase, however, was the estimated $9-$14 million price to obtain the additional land. It was also estimated an additional $1.8 million would be required for fencing. After several years of delays, this last acquisition was finally acquired in 2015.


Wind Cave is known for its rare form of calcite formations known as boxwork which is rarely found anywhere else in the world.

Throughout the several changes in the original surface boundary that was initially surveyed by Thorn, the park slightly decreased on the west side, but has greatly increased to the north and east. The original 10,522 acres has today expanded to 33,924 acres. The original perimeter of 17 miles has increased to 38 miles. The Wind Cave National Park boundary now includes all or parts of 64 different sections in four different townships.

In 1965, the known length of the cave passageways was just over 10 miles. Through the compilation of all known survey data in 1984, an accurate map formed the foundation from which expanded exploration would take place. Today, exploration and surveying within the cave continues by using a hand compass, inclinometer, laser distance measurer, and notebook. The work is tedious with the average distance between measured points being only 20 feet. The current underground map was produced by compiling over 27,000 measurements and has now grown to include over 140 miles of multi-tiered passageways. At least one room has now been laser scanned and additional work is being planned. If history holds true, there is every indication this 115-year-old national park will continue expanding both above and below the surface.

About the Author

Jerry Penry, PS

Jerry Penry has been surveying for 34 years, is licensed in Nebraska and South Dakota, and has been employed with Lancaster County Engineering for 21 years. He is also serving his second term on the Board for the Professional Surveyors Association of Nebraska.