The United Nations Educational, Scientific, and Cultural Organization (UNESCO) has identified 582 World Heritage sites that it considers of outstanding universal value. In the United States, there are 20 of these sites; 17 of the 20 are natural sites, described below. The World Heritage site can be found here: http://whc.unesco.org.
Cahokia Mounds State Historic Site, Illinois: Between A.D. 900 and A.D. 1500 the Cahokia site was the regional center for the Mississippian Indian culture. Named for the Cahokia Indians who came after them, Cahokia features the largest prehistoric earthen constructions in the Americas, a testament to the sophisticated engineering skills of Mississippian culture.
Carlsbad Caverns National Park, New Mexico: Carlsbad Caverns National Park is a network of more than 80 limestone caves, including the nation's deepest1,597 feetand third longest. The Lechuguilla Cave is particularly noteworthy for its beautiful stalagtites and stalagmites.
Chaco Culture National Historical Park, New Mexico: Between A.D. 900 and A.D. 1100, the Anasazi built large multistory stone villages and an impressive 400-mile road system in Chaco canyon exemplifying their engineering and construction talents.
Everglades National Park, Florida: The Everglades, or River of Grass as the Seminoles called it, is formed by a river of fresh water 6 inches deep and 50 miles wide that flows slowly across the expanse of land of sawgrass marshes, pine forests, and mangrove islands. More than 300 species of birds live in the park as well as alligators, manatees, and Florida panthers.
Glacier Bay National Park and Preserve, Alaska: The park is made up of a huge chain of great tidewater glaciers and a dramatic range of landscapes, from rocky terrain recently covered by ice to lush temperate rain forest. Brown and black bears, mountain goats, whales (including humpbacks), seals, and eagles can be found within the park.
Grand Canyon National Park, Arizona: The Grand Canyon is among Earth's greatest ongoing geological spectacles. About 65 million years ago in Earth's shifting, a huge area of land was lifted a mile and a half above sea level, forming what is now the Colorado Plateau. For the last 6 to 10 million years, the Colorado River has been slowly carving its way down through the center, exposing the many colorful strata of rock.
Great Smoky Mountains National Park, North Carolina/Tennessee: Place of Blue Smoke was the name given by the Cherokee Indians to these Appalachian Highlands. The forest here exudes water vapor and oily residues which create a smoke-like haze that surrounds the peaks and fills the valleys. The park is one of the world's finest temperate deciduous forests.
Hawaii Volcanoes National Park, Hawaii: It is thought that the Hawaiian islands were created when molten rock pushed through Earth's crust, forming volcanoes. The two most spectacular live volcanoes are Kilauea and Mauna Loa.
Mammoth Cave National Park, Kentucky: Mammoth Cave, as its name suggests, is the world's most extensive cave system, with 345 miles of passages. Water seeping into the cave creates stalactites, stalagmites, and white gypsum crystal formations. Rare and unusual animals, such as blind fish and colorless spiders, demonstrate adaptation to the absolute blackness and isolation.
Mesa Verde National Park, Colorado: In the sixth century, the Anasazi, or Ancient Ones, established villages on the high, flat land in southwestern Colorado. In the late 1100s they began constructing multistory stone apartment houses, or pueblos, tucked on ledges and under rock overhangs.
Olympic National Park, Washington: The park encompasses not only snow-capped Mount Olympus, glaciers, alpine meadows, and rocky Pacific Mountain coastline, but also one of the few temperate rain forests in the world. The luxuriant forest is created by the warm, moisture-laden air from the Pacific meeting the mountains, resulting in a dense, green, jungle-like world.
Redwood National Park, California: Redwood National Park contains the tallest living things on Earth, evergreen trees that grow to 350 feet. Descendants of the giant evergreens that grew during the age of the dinosaurs, redwoods take 400 years to mature. Some of the survivors are more than 2,000 years old.
Taos Pueblo, New Mexico: Pueblo de Taos is thought to have appeared before A.D. 1400 and is the best preserved of the pueblos (communal housing) north of the border. Taos is a remarkable example of a traditional type of architectural ensemble from the pre-Hispanic period of the Americas and is unique to this region. Today Taos is inhabited by the Taos Pueblo Indians, and it is still an active community.
Waterton-Glacier International Peace Park, Montana: The two parks sustain an exceptionally diverse habitat, including wolves, bears, and mountain lions. It also features a wide variety of wild flowers and wildlife, including bighorn sheep and bald eagles.
WrangellSt. Elias National Park and Preserve, Alaska: The park is made up of gargantuan icefields and about 2,000 glaciers that have created a sculpted landscape of valleys, peaks, and lakes. This premier wilderness contains extensive bird, animal, and marine mammal habitats where trumpeter swans, Daal sheep, bisons, and sea lions dwell.
Yosemite National Park, California: Yosemite, located in California's Sierra Nevada Mountains, contains breathtaking panoramas of rugged scenery and a huge variety of plant and animal life. During the last Ice Age the granite bedrock was gouged and shaped into bare peaks, sheer cliffs, rounded domes, and huge monoliths.
