National Park

Established 11/19/1919 Size 146,597.60 acres (593.3 km2) This geologically unique area has colorful sandstone canyons, high plateaus, and rock towers. Natural arches and exposed formations of the Colorado Plateau make up a large wilderness of four ecosystems.[65]

Established 3/1/1872 Size 2,219,790.71 acres (8,983.2 km2) Situated on the Yellowstone Caldera, the first national park in the world has vast geothermal areas such as hot springs and geysers, the best-known being Old Faithful and Grand Prismatic Spring. The yellow-hued Grand Canyon of the Yellowstone River has numerous waterfalls, and four mountain ranges run through the park. There are almost 60 mammal species, including the gray wolf, grizzly bear, lynx, bison, and elk.[63]

Established 1/9/1903 Size 28,295.03 acres (114.5 km2) Wind Cave is distinctive for its calcite fin formations called boxwork and needle-like growths called frostwork. The cave, which was discovered by the sound of wind coming from a hole in the ground, is the world's densest cave system. Above ground is a mixed-grass prairie with animals such as bison, black-footed ferrets, and prairie dogs,[61] and Ponderosa pine forests home to cougars and elk.

Established 1/8/1971 Size 218,200.17 acres (883.0 km2) This park on four main lakes, a site for canoeing, kayaking, and fishing, has a history of Ojibwe Native Americans, French fur traders called voyageurs, and a gold rush. Formed by glaciers, this region has tall bluffs, rock gardens, islands and bays, and historic buildings.[60]

Established 11/10/1978 Size 70,446.89 acres (285.1 km2) This region that enticed and influenced President Theodore Roosevelt is now a park of three units in the badlands. Besides Roosevelt's historic cabin, there are scenic drives and backcountry hiking opportunities. Wildlife includes American Bison, pronghorns, Bighorn sheep, and wild horses.[58]

Established 5/22/1926 Size 199,045.23 acres (805.5 km2) Shenandoah's Blue Ridge Mountains are covered by hardwood forests that are home to tens of thousands of animals. The Skyline Drive and Appalachian Trail run the entire length of this narrow park that has more than 500 miles (800 km) of hiking trails along scenic overlooks and waterfalls of the Shenandoah River.[57]