One of the iron and steel products for which Trenton became best known was wire rope. Originally developed as a stronger and more durable alternative to hemp, wire rope was first successfully produced in America in the early 1840s by John A. Roebling, a recent German immigrant then living in Western Pennsylvania. Early in his career Roebling worked as an engineer on the design and construction of canals and railroads in Pennsylvania. His main interest, however, lay in bridge technology and, in particular, in the development of the suspension bridge. It was in this capacity that he and his Trenton-based company became world-renowned.
John Roebling relocated to Trenton in 1848, lured by the city's advantageous location within the canal and rail network, and by the prospect of an abundant supply of wire from the mills of the Trenton Iron Company and easily obtainable coal from the Lehigh Valley. He set up his wire rope factory on the outskirts of Trenton, adjacent to the Delaware and Raritan Canal and Camden and Amboy Railroad. Roebling rapidly expanded his works to meet an increasing national demand foe cable, rigging and wire fencing. A demand that continued through the Civil War Era with the Union's need for cable and rope for military bridges and ship.
The firm's long-term reputation rested primarily on its role as a designer, manufacturer and builder of suspension bridges. From John Roebling's first commission, the construction of a suspension aqueduct over the Allegheny River in 1844 through the mid-20th Century, many of the country's premier bridges display the stamp of the Roebling firm. John Roebling died in 1869, in the midst of designing the Brooklyn Bridge, whereupon the firm reorganized as the John A. Roebling's Sons Company. As this entity, the company continued to grow, employing at its peak at the end of World War I around 10,000 workers at five factories in and around Trenton and in the company town of Roebling, New Jersey. Production extended well beyond the manufacture of suspension bridges to elevator and tramcar cable, wire cloth and electrical wire, but the post-World War II decline in heavy manufacturing eventually resulted in the sale of the firm to Colorado Fuel & Iron in 1953, and the final closure of all the Roebling works in 1973-74.
Links to learn more - Invention Factory, Trenton; Town of Roebling, New Jersey