When the Washington Monument was built in 1884, its height was recorded as 555 feet, 5 1/8 inches. Recently, however, the National Geodetic Survey announced that the tallest all-stone structure in the world is now 554 feet, 7 11/32 inches tall. So, how did the tallest edifice in Washington, D.C. get shorter? One explanation centers on its aluminum tip, which has been struck by lightning many times over the decades. Intrigued? Learn more.