Survivors of the 20th Maine Regiment of Infantry Volunteers gathered at Devil’s Den, just below the famed Little Round Top, on Oct. 18, 1889. Their defense of the hill proved pivotal in the Union’s defenses at Gettysburg and have often been credited with saving the Union. Today marks 161 years since the Battle of Gettysburg on July 1-3 in 1863. Courtesy of the Gettysburg National Battlefield and Museum Archive