Wind Cave National Park gained fame when two cowboy brothers discovered its entrance in 1881, and it eventually came to the attention of the country. Its size, unique geological makeup and above-ground ecosystems helped make it a prominent park.
President Teddy Roosevelt made the cave--which is six miles from the South Dakota town of Hot Springs in the western portion of the state--and the surrounding land into the seventh national park in the nation but the first one that focused on a system of caves.
As the bison herds in the country neared extinction, the park became a preserve for the species. The prairie of the park made an excellent place to reestablish the species, which began in 1912.
Scientists estimate Wind Cave to be some 300 million years old, making it one of the oldest caves known to man.
The constant exploration of the caves has found 142 miles of passages as of October 2009, making Wind Caves the third-longest in the United States and the fourth-longest on Earth.
The caves are famous for what geologists term as "boxwork," which forms when slender calcite blades project off the walls and ceiling to produce a honeycomb effect as they intersect.