South Side Flats in Pittsburgh in Allegheny County, Pennsylvania — The American Northeast (Mid-Atlantic)
The MonCon Railroad
Materials on the Move
| | Rivers of Steel National Heritage Area | |
To increase efficiency, a single-track railroad bridge was put into service in 1887. This bridge was replaced by the 1898 "Y" trestle and 1901 Hot Metal bridges that exist today. The MonCon Bridges made the Jones & Laughlin plant more productive by allowing for the movement of hot iron from the blast furnace plant on the northern side of the river to the open hearth and other steelmaking facilities on the South Side and the movement of steel ingots from the South Side to the rolling mills on the northern side.
Topics. This historical marker is listed in these topic lists: Bridges & Viaducts • Industry & Commerce • Railroads & Streetcars. A significant historical year for this entry is 1885.
Location. 40° 25.714′ N, 79° 57.809′ W. Marker is in Pittsburgh, Pennsylvania, in Allegheny County. It is in the South Side Flats. It can be reached from Three Rivers Heritage Trail. Located on the Three Rivers Heritage Trail behind the Hyatt Hotel on Pittsburgh's South Side. Touch for map. Marker is in this post office area: Pittsburgh PA 15203, United States of America. Touch for directions.
Regionally, this marker is in the American Northeast, in the Mid-Atlantic, in the Ohio River Valley, in Appalachia, and specifically in Northern Appalachia. Globally, it is in North America, the Western Hemisphere, the Western World, and the Anglosphere. Historically, it finds itself in what was once the Viceroyalty of New France, the Haudenosaunee (Iroquois) Confederacy, and one of the original Thirteen Colonies.
Other nearby markers. At least 8 other markers are within walking distance of this marker: Materials Handling (a few steps from this marker); Open Hearth Steel (within shouting distance of this marker); Rivers of Steel (within shouting distance of this marker); Cast Iron Columns (about 400 feet away, measured in a direct line); Making Steel The J&L Way (about 500 feet away); Shaping Steel (about 600 feet away); Hub of Activity (about 800 feet away); Jones & Laughlin Steel Company (approx. 0.2 miles away). Touch for a list and map of all markers in Pittsburgh.

Photographed by Mike Wintermantel, April 20, 2016
2. Interchange
The MonCon had interchange capabilities with the three major rail carriers in the region: the Pennsylvania Railroad (PRR), which operated to the south of the plant, the Baltimore & Ohio (B&O), which operated to the north of the plant, and the Pittsburgh and Lake Erie (P&LE), which intersected the plant and had a large switching yard within the boundaries of the Jones & Laughlin South Side Works site. The P&LE passed under the 110-acre mill site between S. 25th and S. 29th Streets via the South Side Works Tunnel. The tunnel, which is located underneath this site, is presently used by the CSX Corporation.
Credits. This page was last revised on February 2, 2023. It was originally submitted on April 22, 2016, by Mike Wintermantel of Pittsburgh, Pennsylvania. This page has been viewed 982 times since then and 23 times this year. Photos: 1, 2, 3, 4, 5. submitted on April 22, 2016, by Mike Wintermantel of Pittsburgh, Pennsylvania.



