The Sierra Nevada is a mountain range in the western United States, between the Central Valley of California and the Basin and Range Province. The Sierra runs 400 miles (640 km) north-to-south, and is approximately 70 miles (110 km) across east-to-west. Notable Sierra features include Lake Tahoe, the largest alpine lake in North America; Mount Whitney at 14,505 ft (4,421 m), the highest point in the contiguous United States; and Yosemite Valley sculpted by glaciers out of 100-million-year-old granite. The Sierra is home to three national parks, 20 wilderness areas, and two national monuments. These areas include Yosemite, Sequoia, and Kings Canyon National Parks; and Devils Postpile National Monument.