Death Valley National Park is a national park located east of the Sierra Nevada in the arid Great Basin of the United States. Parts of the park are in southern Inyo County and northern San Bernardino County in Eastern California, with a small extension into southwestern Nye County and extreme southern Esmeralda County in Nevada. In addition, there is an exclave (Devil's Hole) in southern Nye County. The park covers 5,262 square miles (13,630 km2), encompassing Saline Valley, a large part of Panamint Valley, almost all of Death Valley, and parts of several mountain ranges. Death Valley National Monument was declared a U.S. National Monument in 1933, placing the area under federal protection. In 1994, the monument was redesignated a national park, as well as being substantially expanded to include Saline and Eureka valleys.
It is the hottest and driest of the national parks in the United States. The second-lowest point in the Western Hemisphere is in Badwater Basin, which is 282 feet (86 m) below sea level. The park is home to many species of plants and animals that have adapted to this harsh desert environment. Some examples include creosote bush, Bighorn Sheep, Coyote, and the Death Valley Pupfish, a survivor of much wetter times. Approximately 95% of the park is designated as wilderness. Its wilderness area covers 4,774 square miles (12,360 km2), making it the largest in the Lower 48 states, and the sixth largest in the United States overall. Death Valley National Park is visited annually by more than 770,000 visitors who come to see its diverse geologic features, desert wildlife, historic sites, scenery, and clear night skies.
Mining was the primary activity in the area before it was protected. The first documented non-Native Americans to enter Death Valley did so in the winter of 1849, thinking they would save time by taking a shortcut to the gold fields of California. They were stuck for weeks and in the process gave the valley its name, even though only one of their group died there. Several short-lived boom towns sprang up during the late 19th and early 20th centuries to exploit minor local bonanzas of gold. The only long-term profitable ore to be mined, however, was borax, a mineral used to make soap and an important industrial compound. Today, borax is an essential component of high-temperature resistant boro-silicate glass products, for example Pyrex cookware. Twenty-mule teams were used to transport ore out of the valley; helping to make it famous and the subject of books, radio programs, television series, and movies.
The natural environment of the area has been shaped largely by its geology. The valley itself is actually a graben. The oldest rocks are extensively metamorphosed and at least 1.7 billion years old. Ancient warm, shallow seas deposited marine sediments until rifting opened the Pacific Ocean. Additional sedimentation occurred until a subduction zone formed off the coast. This uplifted the region out of the sea and created a line of volcanoes. Later the crust started to pull apart, creating the current Basin and Range landform. Valleys filled with sediment and, during the wet times of glacial periods, with lakes, such as Lake Manly.
Note: This is No.9 of the series of articles on popular national parks in US.
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