Gettysburg is a borough in Pennsylvania and the county seat of Adams County, Pennsylvania, the United States. As of the 2020 census, the borough had a population of 7,106 people. Gettysburg was the site of the Battle of Gettysburg, the bloodiest battle of the American Civil War, fought from July 1 to July 3 of 1863. Later that year, on November 19, Presiā¦Gettysburg is a borough in Pennsylvania and the county seat of Adams County, Pennsylvania, the United States. As of the 2020 census, the borough had a population of 7,106 people. Gettysburg was the site of the Battle of Gettysburg, the bloodiest battle of the American Civil War, fought from July 1 to July 3 of 1863. Later that year, on November 19, President Abraham Lincoln traveled to dedicate Gettysburg National Cemetery, where he delivered the Gettysburg Address, a carefully crafted 271-word address considered one of the most famous speeches in history.