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 early Continental Army and the first American president. Standing due east of the Reflecting Pool and the Lincoln Memorial, the monument, made of marble, granite, and bluestone gneiss, is both the world's tallest stone structure and the world's tallest obelisk, standing 554 feet 7 11⁄32 inches (169.045 meters) tall; although taller monumental columns exist, they are neither all stone nor true obelisks.