A Blast from the Past: 7th and Pennsylvania Ave. During World War I Published September 9, 2015Updated November 9, 20221 min readby ghostsofdc Check out this great old photo of 7th and Pennsylvania Ave. during World War I. Washington, D.C., circa 1918. “World War I. Food Administration electric signs, 7th Street and Pennsylvania Avenue N.W.” National Photo Co. Source: Flickr