South Dakota has two Congress-designated national parks = Badlands and Wind Cave. Here's the latter national park, which we did after Mount Rushmore and Custer State Park.
Wind Cave is as impressive above ground as it is below ground - this was the first of many bison.
Prairie dogs are also commonly seen.
This trail leads to the right, where the exit to Wind Cave is. One could safely presume that the cave winds under this small hill.
The visitor center, from which all tours leave. They're very popular, so get there early. We had to wait an hour to go underground, and we were fortunate.
Rob heads to the start of the tour.
Wind Cave is extensively mapped, more than just about any cave on earth, and yet there are hundreds of unmapped miles.
Off we go to the cave!
This is the natural entrance to the cave, which isn't really fit for an adult to enter.
The much more spacious artificial entrance.
When the ranger opened this door, people's hats blew off.
Rob made use of his GoPro inside the cave.
Compared to the tour of Mammoth Cave National Park in Kentucky that I did nearly 4 years earlier, I much preferred this tour.
Coming up = Nebraska!