The Spring Valley neighborhood next to American University is built on top of a World War I-era chemical weapons experiment station. From 1917 to 1920, researchers here cooked up deadly gas weapons and tested them in the nearby fields.

When the US entered World War I in 1917 American University was a struggling institution with 28 students, located in the undeveloped hills above of Washington.

The university's president wrote a letter to "his excellency Woodrow Wilson" offering the school "for such purpose as the Government may desire. The campus may be used either for a camping ground for troops, for gardening and raising products for the Army, or for such other purpose as you may elect."

Secretary of the War Newton Baker took him up on the offer and established The American University Experiment Station, the nation’s largest chemical weapon facility. A thousand chemists were assembled to develop cutting edge Mustard Gas and Lewisite weapons for the nascent Gas Service Section.