Washington Monument in Washington, D.C., is 555 feet tall according to the National Park Service.
The obelisk commemorates George Washington, the Continental Army commander and first president of the United States. Construction began on July 4, 1848, but work stopped in 1854 after funding problems and resumed in 1877. The monument was topped out in 1884 and formally dedicated in 1885.
Its structure includes a tall stone shaft and a pyramid-shaped cap called a pyramidion. An aluminum tip sits at the apex. The monument’s exterior uses marble from different quarries because construction took place in separate phases, producing a visible change in the stone’s color.
Some references give the height as 554 feet because modern surveying and later changes to the ground near the entrance produce a slightly different measurement. The commonly quoted National Park Service figure is 555 feet 5 1/8 inches, usually rounded to 555 feet. It remained the world’s tallest structure until the Eiffel Tower was completed in 1889.