The P&LE Liberty Boro Bridge is a girder bridge across the Youghiogheny River connecting the Pittsburgh industrial suburbs of Liberty and McKeesport, Pennsylvania. In 1968, the Pittsburgh & Lake Erie Railroad undertook a major construction project in conjunction with the B&O Railroad to clear tracks from downtown McKeesport. These tracks caused traffic congestion and posed a safety hazard. As a result, both this bridge and the nearby P&LE McKeesport Bridge were created to direct rail traffic to the west bank of the river, which featured a less confusing street grid.