Pennsylvania State Home Page Right To Know Forms, Publications & Maps PennDOT Home PA State Agencies Online Services Terrestrial Laser Scan Data - Photogrammetry & Surveys Section. Photogrammetric Mapping - Photogrammetry & Surveys Section. The Historic Smithfield Street Bridge over the Monongahela River in Pittsburgh is the oldest through truss bridge in the U.S. Built in1883. Search Bureau of Design Banner