(CBS News) GETTYSBURG, Pa. - Gary Roche has been a battlefield guide at Gettysburg for 18 years.
"I can get very emotional here," said Gary Roche. Emotional because for Roche, Gettysburg is personal.
His tour focuses on the experiences of one man, his great, great-grandfather.
"Not only one soldier but his family how he's rippled through time how he would be honored because he's a true American hero," said Roche.
Sergeant Patrick DeLacy served in the Pennsylvania 143rd infantry. He was right there firing at rebels for Pickett's Charge.
"On this very field we're standing on," said Roche.
Pickett's charge was the decisive battle of Gettysburg with an estimated 6,000 killed and injured.
It was a devastating defeat for the Confederate army.
Roche went through a lot of his life knowing almost nothing about Gettysburg and his ancestor who fought here, but something changed that.
"It was a birthday gift from my wife my 40th birthday and I came to Gettysburg for three days and had that epiphany where, 'Wow. Not only does my ancestor leave a detailed record of what he did here but I had the Medal of Honor that he was awarded a year later in the Civil War," said Roche.
Roche's great, great-grandfather lived to be 79 years old.
Shortly before he died, he wrote about his experience at Gettysburg in the Scranton Times.
Now Roche reads his ancestor's words to battlefield visitors.
Visitors Cordelia Peters and her family expected a history lesson -- but they got much more.
"It was very unreal. It made me emotional, to know how much went on," said Peters.
Roche said he still finds it moving to walk onto the battlefield after all these years.
"I promised myself when I got the license, if it ever became a job I would walk away," said Roche. "Every visitor I take out gets the same entusiam on every tour."
150 years later, Gary Roche is giving meaning to the words of Abraham Lincoln that those who gave the last full measure of devotion here shall not have died in vain.