Gettysburg, PA, is one of the most active paranormal hot spots in the world. This is the place where 94,000 Union troops under General George Meade clashed with 72,000 Confederate soldiers under General Robert E. Lee in what became the bloodiest battle of the Civil War. From July 1 to 3, 1863, more than 51,000 Americans were killed, wounded or went missing.

The Ghost Adventures Crew investigated the following haunted locations around the battlefield.

National Soldier's Orphan Homestead: During the battle of Gettysburg, this building was the headquarters of Union General Howard. In 1866, it was turned into an orphanage and at one time housed 130 boys and girls. The head mistress was Rosa Carmichael, who was infamous for her cruelty and was eventually convicted of child abuse. The orphanage closed in 1877, but Rosa's dark spirit is said to be lurking in the basement, trapped and angry.

Jennie Wade House: On July 3, 1863, 20-year-old Jennie Wade became the only civilian casualty during the Battle of Gettysburg when a Confederate sniper's musket ball smashed through the door on the north side of her house, killing her instantly.

The Gettysburg Engine House (Gettysburg and Northern Railroad): It was here that the Union soldiers made a desperate stand against charging Confederates on July 1, 1863. Confederate dead were haphazardly buried around the scene of the battle by local laborers. The large, metal Engine House was built in 1991, long after the battle of Gettysburg, but it was constructed on the hallowed ground where men died and are likely still buried. Did the construction stir up paranormal activity?

Hunterstown Battlefield: At this site, Union Brigadier General George Armstrong Custer's Cavalry clashed with General Wade Hampton's Division of J.E.B. Stuart's Cavalry on July 2, 1863. Of his 3,500 men, Custer reported 32 dead and wounded. The roughly 2,000 Confederate soldiers suffered 100 casualties. Some Civil War re-enactors have reported strange encounters around this battlefield.