The symbol of the city of Washington DC, this 555-foot (169-meter) marble obelisk on the National Mall honors the nation's first president, George Washington. The cornerstone of the Washington Monument was laid in 1848, but construction was not completed until 1884. About one-third of the way up the obelisk is a visible change in the marble, evidence of the onset of the Civil War. Construction was halted during the war, and when the builders returned to the same quarry to complete the project afterward, enough time had passed to cause a significant change in the color. An emblem of the United States and an icon of the nation, the Washington Monument is a moving sight, its elegant form mirrored in the Reflecting Pool of the Lincoln Monument nearby.