Often confused with the Giant Sequoias, Coastal Redwoods are the tallest trees on Earth, reaching heights of over 368 feet (112 meters). They are also among the widest trees on earth, reaching diameters at their base of over 30 feet (9.3 meters). They are amongst the oldest trees in existence, the oldest on record having lived 2,200 years when it was cut down. There used to be over 2,000,000 acres of redwoods along the West Coast of the United States. Now there is only an estimated 200,000 that remain. Muir Woods National Monument is the best example of an Old Growth redwood forest in the San Francisco area.