The valley of the South Branch of the Potomac River was a middle ground, situated between the all-important middle Shenandoah Valley and the Upper Potomac region with its vital coal resources and the B&O Railroad infrastructure centered around Cumberland, Maryland. Federal or Confederate troops occupied this hill and its surrounding area beginning at least as early as August 1861, and were on the ground for at least part of every year of the war.


Federal forces time and again tried to use this strategic point as a choke hold against raids on the B&O to the north, and as a jumping-off point for their own raids further south. The Fort as it exists today was constructed August–December 1863, by troops under the command of Colonel James A. Mulligan from Chicago, IL. Infantry, cavalry and artillery from West Virginia, Pennsylvania, Maryland and Illinois carried out the labor.

The Fort was constructed from August through December of 1863, by Union troops under the command of Colonel James A. Mulligan, from Chicago, Illinois. infantry, cavalry and artillery from West Virginia, Pennsylvania, Maryland and Illinois carried out the backbreaking labor.

Known locally as Fort Hill, the Fort was to serve as protection for the South Branch Valley from Confederate forces and also as an auxiliary depot to supply numerous Union troops on their expeditions.

The Fort was constructed from August through December of 1863, by Union troops under the command of Colonel James A. Mulligan, from Chicago, Illinois. infantry, cavalry and artillery from West Virginia, Pennsylvania, Maryland and Illinois carried out the backbreaking labor. Known locally as Fort Hill, the Fort was to serve as protection for the South Branch Valley from Confederate forces and also as an auxiliary depot to supply numerous Union troops on their expeditions.