Stumphouse Tunnel grew from plans for a railroad line linking Charleston, South Carolina, and Cincinnati, Ohio, but Stumphouse Mountain's granite proved a formidable barrier after the Blue Ridge Rail Line reached Pendleton by the 1850s. Fifteen hundred tunnel workers and their families lived on the mountain in Tunnel Hill, where many Irish immigrants labored twelve-hour days, six days a week, using sledge hammers, hand drills, and black powder. Tunnel Hill became known as a rough town, and after Father Jeremiah Joseph O'Connell arrived in 1854, he pressed the railroad company to dismiss workers who did not remain sober, built a Catholic church dedicated to Saint Patrick, and established a school for miners' children. In 1850, the German Colonization Society from Charleston organized nearby Walhalla, hoping a major railroad would bring economic opportunity, and its leader, John Andreas Wagener, built a black powder mill at the base of Issaqueena Falls to support the work. The tunnel was planned to extend 5,863 feet, with four shafts for ventilation and simultaneous digging from both sides, and at its deepest point the current tunnel lay 236 feet below the mountain's highest point. Even at peak manpower, workers advanced only 200 feet per month through the relentless granite, and despite continued work amid an unscrupulous construction company, high costs, and unreliable funding, only 1,600 feet were cut from the western opening before state funds ran out in 1859. Before additional money could be secured, the War Between the States began, Tunnel Hill disappeared, and after the war South Carolina could not resume construction, leaving the tunnel unfinished. In the 1940s, Dr. Paul G. Miller of Clemson College recognized that the tunnel's steady 56-degree temperature and 85 percent humidity were ideal for curing blue cheese, and after the process was refined and transferred to the Clemson Agricultural Center, the tunnel and Issaqueena Falls became a recreational destination operated by the City of Walhalla.