A very nice, quite short, outline of the battle of Gettysburg. It's written as a walking tour; I don't think it would be useful as one, but it would be a good introduction if you are going to visit the battle site. There are no pictures, but there are some simple maps. Although short, the author seems to have a special interest in debunking myths and false stories (he's a professor at Princeton and the author of the "Battle Cry of Freedom"), and you can read and enjoy the whole thing in a day or two.