The Puente de Trujillo Alto is a Pennsylvania through truss bridge built during 1939–1941 in Puerto Rico in the Trujillo Alto municipality of Puerto Rico. It was the longest single-span bridge in Puerto Rico. A four-lane concrete bridge was built adjacently during 1983-85 as a replacement, with the historic bridge being slated for demolition, but local protests led to its being kept. The supporting structures and bridge were built by Robert Prann, an engineer who established private practice in Puerto Rico, with steel components manufactured by U.S. Steel.