Pan American Union
National Register of Historic Places

Pan American Union

Washington, District of Columbia County, District of Columbia
Listed
June 3, 1969
Type
Building
Period
Modern
Ref No.
69000298

About this property

The Pan American Union Building is the headquarters for the Organization of American States. It is located at 17th Street Northwest, between C Street and Constitution Avenue, in Northwest, Washington, D.C. The cornerstone was laid on May 11, 1908, by Theodore Roosevelt, Elihu Root, and Andrew Carnegie (who largely financed the building's construction) on the former site of the Van Ness Mansion. The building was dedicated on April 26, 1910. It was designed in the style of a Greek temple, with large exterior stairways leading to palatial bronze gates. The building's roof is covered with Ludowici tiles in a blend of reds. In 1919, the initial meeting of the International Labour Organization was held in the building. Between 1921 and 1922, the building was used for committee and subcommittee hearings throughout the Washington Naval Conference while closely guarded by marines with fixed bayonets. The building was added to the National Register of Historic Places in 1969, and was designated a National Historic Landmark in 2021, for its architecture and its role in international diplomacy. This is where the Carter-Trujillo treaties were signed. Media related to Pan American Union Building at Wikimedia Commons "-- holding: Pan-American Union Building, Washington, D.C. -- Philadelphia Architects and Buildings". www.philadelphiabuildings.org. Retrieved March 18, 2025. "Pan-American Union Building". Archived from the original on October 10, 2012. Retrieved March 18, 2025. "[Plan for front of Pan American Union Building, Washington, D.C.]". www.loc.gov. Retrieved March 18, 2025.

Location

17th St. between C St. and Constitution Ave., NW.
Washington, District of Columbia County, District of Columbia
38.89280, -77.04055

Categories

COMMERCEEDUCATIONPOLITICS/GOVERNMENTARCHITECTURESOCIAL HISTORY
National Register nomination ›
Sources

Property data from the National Register of Historic Places, National Park Service (public domain).

Description adapted from Wikipedia under the Creative Commons Attribution-ShareAlike 4.0 International License.

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Nearby Historic Sites

Lockkeeper's House, C & O Canal Extension (Additional Documentation)
Early Republic
0.1 mi
Constitution Hall
Early Republic
0.1 mi
Memorial Continental Hall
Early Republic
0.1 mi
US Department of the Interior Building
Pre Contact
0.1 mi
American National Red Cross
Civil War
0.1 mi

Nearby Battles

September 11 Pentagon Attack
2001Modern
1.7 mi
September 11 Attacks — Pentagon
2001Modern
1.7 mi

Questions about this property

When was Pan American Union listed on the National Register?

Pan American Union was listed on the National Register of Historic Places on June 3, 1969.

What type of historic resource is Pan American Union?

Pan American Union is classified as a building in the National Register of Historic Places.

What is the period of significance for Pan American Union?

The period of significance for Pan American Union is recorded as the modern era, specifically around 1948.

Can I research the history near Pan American Union?

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