The Rainbow Bridge is an old bridge over Brush Creek approximately two miles west of Riverton, Kansas on former U.S. Route 66, now a county road. The bridge is a single-span concrete Marsh arch bridge and is the sole surviving bridge of this type on the entire length of the former highway. Two other Marsh arch bridges were also located on US-66 in Kansas, both over the Spring River. It was built in 1923. The bridge has often been covered with graffiti, but was recently re-painted white.