The Monongahela Connecting Railroad (MCRR) or Mon Conn is a small industrial railroad in Pittsburgh, Pennsylvania. It was a subsidiary of the Jones & Laughlin Steel Company and a large portion of its work was for its parent company, though it also served other industries along the line. The railroad is possibly best known for its Hot Metal Bridge which was used to carry molten iron across the Monongahela River from J&L's Eliza Furnaces to the Bessemer converters and rolling mills at J&L's South Side facility.

The railroad was also a dieselization pioneer, buying many early diesel locomotives from General Electric and other manufacturers.

The railroad is still in existence, but in much reduced form. The Hot Metal Bridge is no longer in use (it is planned to convert it into a pedestrian bridge) and the railroad serves a few small industrial customers along one bank of the river.

See also

• Monongahela Railway, not to be confused with the Monongahela Connecting Railroad.

External links

• George Elwood's Fallen Flags site MCRR pictures (about halfway down the page).
• Photos of the present-day Mon Conn.