Washington Monument: The 555-Foot Marble Obelisk

Why is it significant?

Stand on the grassy knoll surrounded by fifty American flags and look straight up the sheer white marble faces of the Washington Monument.

Key Facts

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Stand on the grassy knoll surrounded by fifty American flags and look straight up the sheer white marble faces of the Washington Monument. Soaring five hundred and fifty-five feet and five inches into the sky, this iconic obelisk is the tallest freestanding stone structure and the tallest obelisk on Earth, weighing over eighty-one thousand tons without a single piece of steel reinforcement.

Look closely about one-third of the way up the shaft, at around one hundred and fifty feet: notice how the color of the marble suddenly shifts to a distinctly darker shade! Construction began in eighteen forty-eight under architect Robert Mills, but ran out of funds and was halted during the Civil War. For over two decades, the stump stood abandoned.

When construction finally resumed in eighteen seventy-nine under the US Army Corps of Engineers, the original Maryland quarry was exhausted, forcing builders to source stone from a different quarry in Massachusetts, leaving this permanent two-tone line across the monument marking the wound of the Civil War.

In December eighteen eighty-four, builders capped the tip with an aluminum apex weighing one hundred ounces—at the time, aluminum was a precious metal as valuable as silver! Turn north toward the White House and Lafayette Square.