The Francis Scott Key bridge crosses the Potomac River and connect Georgetown on the Washington, DC to Rossyln on the Virginia side. The bridge was completed in 1924. It replaced Aqueduct Bridge as the new Georgetown river crossing. The Aqueduct bridge was final transportation role of the Potomac Aqueduct that connect the C&O Canal and the Alexandria Canal. You can see one of the aqueduct abutments along the towpath just upstream from here.