The Robert Street Bridge is a reinforced concrete multiple-arch bridge that spans the Mississippi River in downtown Saint Paul, Minnesota, United States. The bridge is notable for its complex design that was required to accommodate river traffic, the St. Paul Union Pacific Vertical-lift Rail Bridge crossing underneath it at an angle, and roadways on the downtown side of St. Paul. The bridge is also notable for a monumental reinforced concrete rainbow arch. The rainbow arch not only provides 62 feet of headroom above the river, but also provides a strong aesthetic focus. It was built in 1924–1926 by Fegles Construction Company, Ltd. and designed by Toltz, King & Day. The bridge was added to the National Register of Historic Places in 1989. The bridge as well as Robert Street itself are name