Wind Cave National Park was established in 1903 by President Theodore Roosevelt as the seventh national park. The cave is world-renowned for its calcite boxwork and actually contains 95% of the discovered boxwork formations in the world.
The Lakota Souix spoke of a hole that blew air. They considered Wind Cave as the sacred site where the Lakota first emerged from the underworld. The first documented discovery of Wind Cave was in 1881 by brothers Tom and Jesse Bingham. They heard a sound of wind rushing out from a 10-inch hole in the ground. When Tom looked down into the hole, the wind was blowing out so hard that it blew the hat off of his head. This is known as the natural entrance, and it’s amazing to think that anyone could climb through this tiny opening. The wind exiting or entering Wind Cave blows up to 35 mph depending on the atmospheric pressure outside the cave.
Boxwork is formed from thin blades of the mineral calcite. The boxwork once filled thin cracks in the cave walls, which were of a softer material that eventually dissolved away when the cave was still filled with water, revealing the intricate honeycomb patterns of boxwork. It derives its name from early explorers who thought it looked like post office boxes.
Wind Cave also has little round formations of calcite called popcorn.
There are also a few examples of a delicate structure called frostwork. The cause of frostwork is still under debate. Some scientists believe moist air coated rock surfaces, while others believe it’s caused by water that seeped through the cave walls and then evaporated.
Wind Cave is the world’s fifth longest cave at 137 miles of discovered passageways and an average of four new miles of cave discovered each year. It’s also one of the most complex caves in the world, with the entire 137 miles of cave stacked in a 3-dimensional swiss-cheese maze under only one square mile of surface area.
The Wind Cave itself is arguably the primary focus of most visitors to the national park. But on the surface, we were delighted to discover 33,847 acres of grasslands in what is the largest remaining natural mixed-grass prairie in the United States.
There are 30 miles of established hiking trails on the surface, but visitors are also allowed to explore off-trail as desired. We started hiking on a trail but eventually just wandered where our heart took us. Along the way we spotted a large bison enjoying some lunch.
Bison can run over 30 miles per hour and are known to charge when provoked. Since this bison wasn’t in a cage, we kept a respectful distance.
We saw a few pronghorns resting and feeding in the prairie. Though these closely resemble antelopes and are often mistakenly called “pronghorn antelopes,” pronghorns are actually a different species.
One thing we love about grasslands is the wide-open vistas that reach to the horizon in all directions.
The ranger said we were one of the lucky few visitors to spot a herd of elk. This is likely because we were hiking off trail, where we didn’t see another human all day.
We stopped for lunch on a hill overlooking the prairie. From our higher vantage point, we could see a bunch of bison, pronghorn and prairie dogs.
Wind Cave National Park has a large population of black-tailed prairie dogs. Of course these furry little dogs are not actually canine, but rather a burrowing rodent related to ground squirrels.
Prairie dogs live in large communities called “towns.” There were many prairie dog towns right along the road, giving us an up-close view of these cute little critters. When our car would approach, the prairie dogs along the road would rush to their holes, then jump up and down with a loud SQUEAK to alert their neighbors of our presence.
These two juvenile prairie dogs (prairie puppies?) are so cute that we wanted to jump out of the car and give them a hug. But of course we didn’t, because prairie dogs are wild animals that can bite when they feel threatened. Prairie dogs can also transmit diseases that are harmful to humans including the plague. Cute but deadly.