The fort at Elkmont we always called Suplhur Trestle. It's directly southwest of the trestle. You can park along the track in Elkmont, hike down the track & see the fort after you cross the trestle...or you could see the fort until someone built a house right smack on top of it! Before that it was beautiful with deep trenches & fortifications including outer trenches, rifle pits and a place to drive wagons in. Reading any of the Forrest books will give you a complete description of the action here & it's an absolutley amazing story.