Camp Sumter was opened by the Confederacy in Andersonville, Georgia, in March 1864. A 17-foot high stockade was built on 16.5 acres, sandwiched between two hillsides. The "Stockade Branch" stream wound through the hillsides and provided water for the inmates. Prisoners would scoop water from the stream with tin cups attached to poles. They were ordered to dip the water while remaining behind a "deadline." Crossing the line meant death. The stockade's pilings cramped the water flow, turning 5 acres of the space into inhabitable marsh forcing the prisoners to trudge through waist-high mud to access the water. The water became contaminated from human waste, laundered clothes and grease from the cook house. Sixty percent of the prisoners died at Camp Sumter in the summer of 1864. With additional inmates, the prison reached its peak population of 32,000 or one person per 25 square feet and 13,000 prisoners died at Camp Sumter during the Civil War. Almanacs reflect that on August 9, 1864 the afternoon temperature approached 93 degrees as a severe thunderstorm hit the camp. The torrential rain rolled across the hillside, Stockade Branch overflowed, broke the stockade's pilings and created a flash flood. Sentries contained the prisoners by firing cannons as guards, stood in the storm, preventing escapes while scrambling to repair the stockade. The next morning the filth was washed away and prisoners noticed that a single lightning bolt struck a pine stump inside the prison camp. That bolt of lightning also penetrated an underground spring that spewed fresh water to prisoners inside the stockade. A few weeks later, the prisoners were relocated as Union General William Sherman burned Atlanta, located 125 miles from the camp.