As Lt. Gen. Richard S. Ewell's Confederate Second Corps advanced on Harrisburg in June 1863, Union Maj. Gen. Darius N. Couch, charged with the defense of the city, recognized the need for a series of defensive fortifications to be constructed on Bridgeport Heights. Shortly after Couch arrived in Harrisburg, local citizens were encouraged to volunteer to build the defenses. On June 15, the work began in earnest, with a reported 1,000 men patriotically assisting. By the following morning, however, only a fraction of the civilian volunteers remained. Their places were filled by worker from the Pennsylvania Railroad and Canal, who received a daily wage of $1.25.
Constructed hastily by a workforce with little military experience, the fortifications were not overly impressive from a military standpoint and had numerous potentially deadly defects in battle. Christened Fort Washington, the earthworks measured about two hundred by six hundred yards. Unfortunately, Fort Washington was constructed on the lower militarily-unfavorable portion of Bridgeport Heights. To protect the misplaced fortress, a smaller earthwork called Fort Couch was erected a short distance farther west at what is now the intersection of 8th and Indiana Streets.
Camp Couch - separate from Fort Couch - was established between the two forts. Many New York National Guard and Pennsylvania Militia regiments were encamped there throughout the summer of 1863. The steepness of Bridgeport Heights, however, made the hill a treacherous location for a camp. By one account, eight horses and twenty men were required to haul just one cannon up to the encampment. Many complaints survive from the infantrymen in Camp Couch, who slid down the steep slope during their slumber. The difficult terrain complicated many ordinary tasks, such as drill, for the soldiers. "We can show no fancy appearance of [c]amp", wrote one New York soldier in Camp Couch, "as it is on the summit of a very high hill... above the Susquehanna. There is not a level spot, and every parade drill or sentry walk has to be [done] with one foot much lower down than the other."