From Recreation.gov: "The Washington Monument dominates the United States Capital skyline as a symbolic tribute to George Washington's military leadership, humble statesmanship, and Presidential fortitude and wisdom. Constructed from marble, granite and gneiss, the Monument is the world's tallest free-standing stone structure, towering more than 555 feet (169 meters)."
Inserted into the interior walls are 193 memorial stones presented by individuals, societies, cities, States, and nations of the world.
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