Overview
The Washington Monument is an obelisk on the National Mall in Washington, D.C., built to commemorate George Washington, a Founding Father of the United States, victorious commander-in-chief of the Continental Army from 1775 to 1783 in the American Revolutionary War, and the first President of the United States from 1789 to 1797. Standing east of the Reflecting Pool and the Lincoln Memorial, the monument, made of marble, granite, and bluestone gneiss, is both the world's tallest predominantly stone structure and the world's tallest obelisk, standing tall, according to the U.S. Geodetic Survey measurements in 2013–2014. It is the tallest monumental column in the world if all are measured above their pedestrian entrances. It was the world's tallest structure between 1884 and 1889, after which it was overtaken by the Eiffel Tower, in Paris. Previously, the tallest structure was the Cologne Cathedral.
Construction of the presidential memorial began in 1848. The construction was suspended from 1854 to 1877 due to funding challenges, a struggle for control over the Washington National Monument Society, and the American Civil War. The stone structure was completed in 1884, and the internal ironwork, the knoll, and installation of memorial stones was completed in 1888. A difference in shading of the marble, visible about or 27% up, shows where construction was halted and later resumed with marble from a different source. The original design was by Robert Mills from South Carolina, but construction omitted his proposed colonnade for lack of funds, and construction proceeded instead with a bare obelisk. The cornerstone was laid on July 4, 1848; the first stone was laid atop the unfinished stump on August 7, 1880; the capstone was set on December 6, 1884; the completed monument was dedicated on February 21, 1885; and it was opened October 9, 1888.
The Washington Monument is a hollow Egyptian-style stone obelisk with a column surmounted by a pyramidion. Its walls are thick at its base and thick at their top. The marble pyramidion's walls are thick, supported by six arches: two between opposite walls, which cross at the center of the pyramidion, and four smaller arches in the corners. The top of the pyramidion is a large, marble capstone with a small aluminum pyramid at its apex, with inscriptions on all four sides.
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