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 American president. Standing almost 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 tall. It is the tallest monumental column in the world if all are measured above their pedestrian entrances, but two are taller when measured above ground, although the latter are neither all stone nor true obelisks.
Construction of the monument began in 1848, and was halted from 1854 to 1877 due to a lack of funds, a struggle for control over the Washington National Monument Society, and the intervention of the American Civil War. Although the stone structure was completed in 1884, internal ironwork, the knoll, and other finishing touches were not completed until 1888. A difference in shading of the marble, visible approximately 150 feet or 27% up, shows where construction was halted.