One of the few times that PRR deviated from its Standard in the construction of interlocking towers was the construction of MG Tower. MG, standing for "Mid Grade" was constructed to handle an extreme increase in train volume during World War II. The introduction of the tower and interlocking gave the railroad more flexibility to route trains on the East Slope of the Allegheny Mountains. Used for nearly half a century, this brick structure became obsolete with the introduction of centralized train control by the mid 1990s. By 2021, Norfolk Southern deemed the structure unnecessary and begun to deconstruct the tower.