Discussion relating to the B&O up to it's 1972 merger into Chessie System. Visit the B&O Railroad Historical Society for more information. Also discussion of the C&O up to 1972. Visit the C&O Historical Society for more information. Also includes the WM up to 1972. Visit the WM Historical Society for more information.
  by TheOneKEA
According to this Wikimapia article, Halethorpe Tower was open from 1917 to 1985 and presided over a 4-track interlocking allowing access to all tracks on the Baltimore Terminal Sub. How often would this interlocking have been used for switching traffic prior to its closure? Did the B&O regularly switch traffic here or would the dispatchers switch traffic at Carroll or Baileys instead? I’m curious to know if the dispatching usually had traffic going to the OML or the Capital Sub on the necessary track prior to Halethorpe.
  by mmi16
While Halethorpe tower stopped being a manned location in 1985, it continued to be a CTC control Point until about 2006 when the St. Denis control point was established. The power switches from Halethorpe were moved to Connellsville once the St. Denis control point became operational.

Trains are crossed over at Halethorpe and/or St. Denis in accordance with the needs for the operation of Baltimore Terminal. The establishment of the St. Denis control point lengthened the distance between the Lansdowne control point and allowed for the holding of larger trains on the siding between Lansdowne and St. Denis. Trains get held for a number of reasons. Crews, space at destination and a number of other reasons. Consol Coal trains are normally held on the siding until space is available to the Consol facility on the NS in the Canton area of the city.

Since Mt.Clare Yard is no longer a classification yard there is little traffic the comes out of Mt. Clare on what were once #3 and #4 Main Tracks. Coal/empty trains to Curtis Bay use #3 track from Curtis Bay Jct. to St. Denis through West Baltimore and Lansdowne.

At St. Denis - East and West bound trains on any track can be routed to any track in their direction of movement - Eastbound trains on OML, #1 or #2 tracks can be routed to #1, #2, #3 tracks or the Halethorpe Siding; by the same token trains on any of those tracks can be routed Westbound to #1, #2 or the OML.