Built to honour George Washington, the United States’ first president, the 555-foot marble obelisk towers over Washington, D.C. First in War, First in Peace, First in the Hearts of his Countrymen Built to honor George Washington, the United States’ first president, the 555-foot marble obelisk towers over Washington, D.C. History of the Washington Monument. 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.