Gettysburg is one of the battle fields I have visited a couple of times. Most of the field is as it was on the day of the battle. I am no expert tactition I was never a soldier, but when you stand on that battlefield you can really see the value of the high ground, and how amazingly brave the men on both sides were.
If you stand at the stone wall at the point the confederates were aiming for on the third day and look across the way at the woods you wonder how anybody made it back from that charge. It truly leaves you speechless.