Philadelphia, Wilmington and Baltimore Railroad Bridge No. 1, Railroad bridge in Grays Ferry, Philadelphia, US.

The Philadelphia, Wilmington and Baltimore Railroad Bridge No. 1 is a steel truss railway bridge that crosses the Schuylkill River in Grays Ferry, Philadelphia. The structure features a movable span design that allows water traffic to pass underneath without obstruction.

The bridge was built in 1901 by the American Bridge Company to replace an earlier wooden structure from 1838. The new steel bridge was designed to handle the expanding railway demands of the region.

The Historic American Engineering Record documented the bridge after 1968, preserving its architectural details and construction methods for future generations.

Access to the bridge is limited for safety reasons since it is no longer in active service. The structure can best be viewed from the surrounding riverbanks or from the water for a clearer perspective of its design.

A cylindrical stone pier in the river's center supported the rotating mechanism and was protected by a wooden pile fender system. This design demonstrates early 20th-century engineering solutions for managing river traffic without compromising the bridge structure.