The original Duquesne Wharf was constructed in 1896 to create a direct river-to-rail route between West Virginia, Kentucky, and Pennsylvania coal mines and Great Lakes commerce. Driven by a coal-fired, steam-operated, revolving crane, this dock was replaced in 1914 with a second facility equipped with two cantilevered traveling cranes.

Upgrading Duquesne Wharf, Union Railroad replaced the traveling cranes in 1964 with a revolving clamshell bucket crane. In 1978, a continuous bucket unloader was added, making Duquesne Wharf the only dock facility in the region offering dual unloading capabilities. In 1999, the revolving crane was replaced with a new state-of-the-art, hydraulic equilibrium crane.

Union Railroad began as part of the Lake Erie to Pittsburgh Mills rail line, in 1896. Originally extending from East Pittsburgh to Hays, a distance of six miles, Union Railroad soon expanded to include 13 branches with an aggregate length of 14 miles. In 1897, the first Union Railroad train interchanged with the Pittsburgh, Bessemer & Lake Erie Railroad at East Pittsburgh.

Today, Union Railroad includes 65 miles of main track and approximately 200 miles of yard tracks and sidings. Union Railroad provides general rail transport and switching services to the steel industry, barge-to-rail transport of coal and bulk commodities at Duquesne Wharf, and rail interchange service to automotive, chemical, and aggregates customers.

In 1988, Union Railroad joined Transtar, Inc., a holding company comprised of rail and water carriers, river dock facilities. Transtar companies extend from Pittsburgh's Monongahela Valley on the east to the greater Chicago metropolitan area on the west: and to Alabama's steel making center in the south.