Keystone Bridge Co.

of Pittsburgh, Pennsylvania

Frisco Bridge (Shelby County, Tennessee)
Steel fabrication, 1892
Cantilevered through truss railroad bridge over the Mississippi River at Memphis
Open to railroad traffic

Keystone Bridge (Park County, Colorado)
Built ca. 1870
Through truss bridge over North Fork South Platte River at Bailey
Open to pedestrians only

Windsor Harbor Bridge (Jefferson County, Missouri)
Built 1875
Wrought-iron through truss over Rock Creek at Kimmswick in Imperial
Open to pedestrians only