Boxwork is a type of speleothem (cave formation) made of thin blades of calcite that project from cave walls and ceilings, forming a honeycomb pattern. The fins intersect one another at various angles, forming "boxes" on all cave surfaces. Boxwork is largely confined to dolomite layers in the middle and lower levels of Wind Cave. As a matter of fact, ninety-five percent of the world's boxwork is found in Wind Cave.

Badlands National Park is a treasure trove of fossils, including these small, spherical, fossil dung beetle balls. Yup, that's right, fossilized dung beetle balls around 30 million years old, during a time when the landscape was a semi-tropical grassland with open forests.

According to the National Park Service, "There are 400-450 bison in Wind Cave National Park. They are grazers and usually found on the grasslands. There are several good places to see bison along U.S. 385, S.D. 87, and primitive roads N.P.S. 5 & 6. Since the bison roam as they eat, they are never in one place for very long."

Gigantic carvings of four revered presidents on a cliff face are not the only draws to Mount Rushmore National Memorial. Many birds live within and around this area, including the cheerful orange and yellow western tanager.

Reserve a spot on the Discovery Tour at Jewel Cave National Monument in South Dakota, and you'll be able to explore the cavernous target room during this 20-minute, accessible tour of a portion of Jewel Cave. According to the National Park Service, "During the Discovery Tour, you will see two types of calcite crystals commonly named nailhead spar and dogtooth spar, which are the "jewels" of Jewel Cave. You will also see manganese and paleofill, which are not cave formations, but are important to the geology of Jewel Cave.

Located just off of Exit 116 along Interstate 90 near Wall, South Dakota and surrounded by short grass prairie sits the Delta-09 missile silo, where "from 1963 until the early 1990s, the missile silo at Delta-09 contained a fully operational Minuteman Missile, bearing a 1.2 megaton nuclear warhead. The Delta-09 missile silo was one of 150 spread across western South Dakota. In total there were 1,000 Minuteman missiles deployed from the 1960's into the early 1990's. Visitors can now tour the site daily."

Badlands National Park is one of several National Park System units located within the boundaries of South Dakota. Stunning scenery may be viewed all along the road, and you should stop at all the view areas for different perspectives of this 244,000-acre park.

According to the National Park Sevice, "In North America, both 'bison' and 'buffalo' refer to the American bison (Bison bison). Generally, 'buffalo' is used informally; 'bison' is preferred for more formal or scientific purposes. Historians believe that the term 'buffalo' grew from the French word for beef, 'boeuf.' Some people insist that the term 'buffalo' is incorrect because the 'true' buffalo exist on other continents and are only distant relatives."

"Blue hour" is a term given to that time prior to sunrise and just after sunset, when the sky and landscape are bathed in swaths of blue, purple, pink, and mauve. During that time (which really doesn't last an hour - more like a few minutes), you might even see the atmospheric phenomenon known as the "belt of Venus," a line of deep blue and dark pink parallel to the horizon. A great place to view sunrise, sunset, and blue hour is at a pullout immediately after the turnoff from Colorado State Highway 150 onto Lane 6 N toward Mosca.

If you bring along your camera (and you should), you can capture not only wide-angle shots of this national park, but also telephoto close-ups of the sinuous sand dunes. Early morning or later in the afternoon are great times to capture light and shadows to give the dunes some depth. Telephoto shots bring the viewer closer to these sand dunes for a better look. You might even want to include people in some of your shots, allowing your viewer a better idea of just how large and tall these sand dunes are in addition to adding a little familiar reference.