The Maryland Midland Railway (reporting mark MMID) is a Class III short-line railroad operating approximately 63 miles of track in central Maryland. It was originally headquartered in the former Western Maryland Railway station in Union Bridge, Maryland: it has since moved to a new facility across from the old station. The railroad has been 87.4% owned by Genesee & Wyoming since 2008, with Lehigh Cement (the largest shipper on the line) retaining a 12.6% interest.