The Lake Tahoe is one of the deepest and clearest lakes in North America, sitting more than 6,000 feet above sea level in the Sierra Nevada. Straddling the California–Nevada border, Tahoe fills a large fault basin later deepened by glaciers, giving it steep underwater walls and remarkable clarity. Its great depth allows cold water to persist year-round, slowing algae growth and helping maintain its famous blue color. Geography explains why Lake Tahoe looks and behaves the way it does. Mountains