Washington Monument, Washington DC USA
The Washington Monument is an obelisk on the National Mall in Washington, D.C., built to commemorate George Washington, once commander-in-chief of the Continental Army and the first President of the United States. Located almost due east of the Reflecting Pool and the Lincoln Memorial,[2] the monument, made of marble, granite, and bluestone gneiss,[3] is both the world's tallest stone structure and the world's tallest obelisk, standing 554 feet 7 11⁄32 inches (169.046 m) tall according to the National Geodetic Survey (measured 2013–14) or 555 feet 5 1⁄8 inches (169.294 m) tall according to the National Park Service (measured 1884).[A] It is the tallest monumental column in the world if all are measured above their pedestrian entrances.[B] It was the tallest structure in the world from 1884 to 1889.