Jewel Cave National Monument
Jewel Cave National Monument  is in the Black Hills of South Dakota. The cave is the second longest known cave in the world, and going. In 2006 more than 136 mi (219 km) of passage have been surveyed. The cave received its name after the large amounts of calcite (calcium carbonate) crystals found in the cave. The cave offers plenty of underground beauty, however, offers a variety of things to do on the surface.
Two brothers, Frank and Albert Michaud, filed a mining claim in 1900. This the first written record of Jewel Cave. The brothers intended to transform the cave into a tourist attraction. The remote location of the cave precluded it from being a commercial success. On Feb 7, 1908, US President Theodore Roosevelt set aside the cave as a National Monument following a local movement to preserve the cave.
Jewel Cave National Monument is in a large pine forest.
Flora and fauna
There are many wildflowers in the National Monument. As with many national parks and monuments, there are non-native species that the managers actively work to remove. This work restores the area to its original condition and removes the threat non-native species often present to the native species.
Where there is a cave, there is often bats. Bats use caves to hibernate during the winter. Elk, mule deer, rabbits, squirrels, a variety of snakes, hawks, eagles, and other birds can be found in the area.
The cave itself is a constant, somewhat damp, 49 degrees.
The nearest airport is in Rapid City located 54 mi (87 km) from the visitor center. Car rental services are available.
The only fees are for the various cave tours.
Walking paths and trails are found above ground.
The area is rebuilding itself after the Jasper fire. Visitors can see this process.
A number of cave tours are offered, including wild tours. Tours are first come, first served. Tour sizes are limited in size. It is not uncommon for tours to sell out during the summer months, so it is advisable to call ahead and reserve.
The cave is 49°F (9.4°C) year round. Wear appropriate clothing and footwear.
Other than vending machines, there is no food service at the cave. The nearest restaurants are in Custer or Newcastle, Wyoming. Food and drink are not allowed in the cave.
There is no lodging in the National Monument. The nearest accommodations are in Custer.
There is no camping in the National Monument.
Jewel Cave NM is surrounded by the Black Hills National Forest, and, as with nearly all U.S. National Forests, you can pitch a tent pretty much anywhere as long as you get away from the road and do not go down any roads marked as private.
A guided tour of the cave is quite safe. However, it is wise to stay with the tour guide, as unmarked parts of the cave are not lit and it is easy to get lost.