Observatory Hill Historic District

Situated on a prominent hill in Foggy Bottom, the buildings of the Observatory Hill Historic District represent important developments in science and national intelligence.

Although L’Enfant anticipated that this hill overlooking the Potomac would be used for defensive battlements, it was instead set aside for a national university that never materialized. The site remained a lightly wooded military campground and overgrown meadow until 1842, when President Tyler selected the site as the permanent home of the Depot of Charts and Instruments (established 1830), and authorized the Navy to construct a National Observatory to make the astronomical observations essential for navigation.

As the home of the nation’s first Naval Observatory, which opened in 1844 and remained in operation until 1893, Observatory Hill led the world in scientific research, witnessing significant developments in oceanography and astronomy. After the Observatory moved to Massachusetts Avenue in 1893, the campus became the home of the Naval Museum of Hygiene, the Naval Medical School, and later the Washington Naval Hospital. During this period, the institutions on Observatory Hill made important advances in the fields of health, medicine, and education. Furthermore, Observatory Hill served as the home of the U.S. Public Health Service’s Hygienic Laboratory from 1903 until 1930 and of the National Institute of Health (NIH) from 1930 to 1940, during which period it witnessed important discoveries in the study of infectious diseases.

Shortly after the NIH relocated to its new campus in Bethesda, the buildings became operated by a new agency, the Office of the Coordinator of Information, which became the Office of Strategic Services (OSS) in June 1942. The newly-created wartime agency was dedicated to the acquisition and analysis of intelligence information and was led by William J. Donovan, who had his offices in Room 109 of the East Building.

As the OSS headquarters from 1941 to 1945, and then as the headquarters of the Central Intelligence Agency (CIA) from 1945 to 1961 after the agency transformed once more, Observatory Hill’s E Street Complex served as the command and control center for intelligence activities in the U.S. Key decisions of national and international significance during World War II, the Korean War, and the early Cold War were made on the campus, which witnessed the evolution of early American intelligence gathering and analysis.

Between 1844 and 1961, as the home of multiple significant institutions, Observatory Hill has been the seat of many crucial developments in science, health and medicine, politics, and international relations. As the site of the current-day Potomac Annex, the buildings of Observatory Hill are now primarily administered by the U.S. Department of State, although the Navy continues to use some structures onsite.

DC Inventory: October 27, 2016
National Register: January 12, 2017



23rd and E Streets NW