A place where fighting happens, especially during a war, can be called a battlefield. If you visit Gettysburg, Pennsylvania, you'll see a famous Civil War battlefield.
There are many Civil War battlefields in the southern United States, and New England is the site of several Revolutionary War battlefields. While the physical land where a battle is fought is the most common kind of battlefield, there are also figurative battlefields, like a classroom in which competing ideas are angrily hashed out. The equivalent word in Old English is wælstow, or "slaughter-place."