located in the northwestern USA in Wyoming, Montana, and Idaho. Founded in 1872, it is the oldest national park in the country. Area, about 9, 000 sq km (1970). It is located in the Rocky Mountains on a volcanic plateau at an elevation of 2, 200–2, 500 m.
In geological structure the plateau of Yellowstone NationalPark is a subsidence that dates from the Paleocene and is filledwith later volcanic and glacial deposits. Points of interest includemore than 3, 000 geysers (the highest stream of the Excelsiorgeyser is up to 90 m) and hot springs and many mud volcanoesand lakes. Other interesting sights are the Grand Canyon of theYellowstone, 360 m deep and 20 km long; waterfalls up to 94 mhigh; and petrified trees buried under volcanic ash. There is alsoconiferous forest (a number of species of pine, fir, and spruce, with some alder, birch, and aspen). The park is inhabited bybison, American black bear, deer, grizzly, elk, pronghorn, big-horn sheep, and coyotes and trumpeter swan, bald eagle, andwhite pelican (about 200 species of birds). The principal touristseason is June through August.