During the First World War, she persuaded 64th United States Congress to approve and fund the construction of a "National Sylvan Theater" at its present site at the Washington Monument in 1916.

It was built and maintained by the United States Department of War in its administration of the park system of the District of Columbia, while performances had to receive the approval of the Office of Public Buildings and Grounds.

A special electric cable was laid to provide current for a series of larger projector lamps, which, when placed on platforms, were meant to furnish light for the performances.

[11] Today, the site is a popular venue for free military concerts, musicals, Shakespeare plays, puppet shows and ballet during the spring, summer and fall.

The bands of each of the four service branches perform (different nights) free al-fresco concerts, typically including military marches, patriotic numbers, and some classical music.

[13][14] Every August, Tchaikovsky's 1812 Overture is performed with real cannon at the Sylvan Theater by the Presidential Salute Battery of the 3rd U.S. Infantry (The Old Guard) in what is perhaps the United States Army Band's most popular regular engagement.

[19] The theater has also been the site for religious services, such as an outdoor Mass in the 1950s that featured a sermon by Archbishop Fulton J. Sheen,[20] and the public talk of Kirpal Singh during his 1963 visit to Washington D.C.[21]