The MMID was incorporated in 1978, and ran its first train in May 1980.
Until Oct. 1983, the MMID ran on 17 miles of leased MD state track,
between Taneytown and Walkersville. From Oct. 1983 to Aug. 1988,
part of the former WM East Sub. from Highfield to Emory Grove was
purchased from CSXT or the state
of MD. --- Currently, the MMID owns 70 miles of track, of which 63 miles
are in service, and operates 10 EMD built locomotives.