The siege of Fort Pulaski concluded with the battle of Fort Pulaski fought April 10–11, 1862, during the American Civil War. Union forces on Tybee Island and naval operations conducted a 112-day siege, then captured the Confederate-held Fort Pulaski after a 30-hour bombardment. The siege and battle are important for innovative use of rifled guns which made existing coastal defenses obsolete. The Union initiated large-scale amphibious operations under fire.