Built before the Civil War by the US Army, Fort Pulaski was located near the mouth of the Savannah River. On April 10th 1862 Union Captain Quincy Adams Gillmore an engineer replaced artillery on the main land with the new rifled artillery and began a bombardment. Within a few hours the bombardment had caused a breach in the southeast side of the fort. Some of the shells started to get to the traverse that shielded the magsazine, realizing that it could explode confederate Colonel Charles H Olmstead surrendered shortly after two pm on the 11th.
Some other places you can look for more information
The Battle of Fort Pulaski