Sierra Nevada,a mountain range in the United States. It lies almost entirely in California; a small section near Lake Tahoe juts into Nevada. The range is some 400 miles (640 km) long and 40 to 80 miles (65 to 130 km) wide. For most of its length it rises abruptly from the Great Basin on the east and slopes gently toward the Central Valley of California on the west. In the southern section, called the High Sierras, are 11 peaks more than 14,000 feet (4,270 m) high. One of these is 14,494-foot (4,418-m) Mount Whitney, the highest point in the United States outside Alaska.

Numerous rivers originate in the Sierra Nevada. Most of them flow westward to the Central Valley. Lumbering and grazing in the range are of major economic importance. The Sierra Nevada contains some of the finest scenery in the United States, including that of Yosemite, Sequoia, and Kings Canyon national parks and Lake Tahoe.