Federal Triangle

The Federal Triangle is a triangular area in Washington, D.C. formed by 15th Street NW, Constitution Avenue NW, Pennsylvania Avenue NW, and E Street NW. Federal Triangle is occupied by 10 large city and federal office buildings, all of which are part of the Pennsylvania Avenue National Historic Site. Seven of the buildings in Federal Triangle were built by the U.S. federal government in the early and mid-1930s as part of a coordinated construction plan that has been called "one of the greatest building projects ever undertaken" and all seven buildings are now designated as architecturally historic. The Federal Triangle Washington Metro station serves Federal Triangle and the surrounding area.

The name "Federal Triangle" appears to have been a journalistic invention. The press made reference to a "Pennsylvania Avenue Triangle" as early as November 18, 1926, and use of this name continued as late as June 1929, but it was more common for the news media to refer to the area as "the Triangle" by 1927. This name was in use by 1928, even by government officials, and still used as of late 1934.

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