A very well made film with a cast of thousands including Tom Berenger, Martin Sheen, Stephen Lang and Richard Jordan following the American Civil War battle of (you guessed it) Gettysburg.
The version I watched came in at just under four hours and my only criticism of it overall would be that unless you are a civil war reenactment nut, a lot of the minor skirmishes and events leading up to the Gettysburg battle portrayed in the film make it rather confusing. Sure I know the basic details of the battle, but packing in every little tiny incident, as Gettysburg does, leaves you a bit lost after a few hours.
My recommendation is if you want to really enjoy this film read this link first (not after you watch the film as I did) to brush up on the history a bit.