A starry view from a forest of giant Sequoia trees in the Yosemite National park, California. Sequoias are among the largest and tallest trees on Earth. They grow to an average height of 50-85 m and 6-8 m in diameter. Record trees have been measured to be about 95 m (311 ft) in height and 17 m (57 ft) in diameter. The oldest known Giant Sequoia is 3500 years old and many of the largest are over 2000 years old.