The grand marble structure next to the White House is the headquarters for the Organization of American States, an international diplomatic body that promotes peace and commerce between North and South American nations.
The OAS building was made possible by a philanthropic donation from Andrew Carnegie, a longtime supporter of world peace. The magnificent design was put together by Albert Kelsey and Paul Cret and quickly drew praise as one of the most elegant pieces of architecture in Washington, D.C. (Back then the OAS went by a different name, the Pan American Union).
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