The Armstrong Tunnel connects the Tenth Street Bridge to Forbes Avenue Uptown. It opened in 1927, three years after the Liberty Tubes. Unlike most of our tunnels, it has a curve in the middle. It also retains its pedestrian walkway, which the Liberty Tubes lost in the 1970s. The impressive portals (we see the north entrance here) were designed by Stanley L. Roush, who worked on a number of transportation-related projects, including the Allegheny County Airport and the portals to the Smithfield Street Bridge.
