This map is actually of Camp McDonald in Big Shanty (Kennesaw), Ga.
Camp McDonald was a camp of instruction through which many of the ANV Georgia troops went through.
GMI cadets did act as training officers for the volunteers which I always thought amusing. Here you had teenage cadets training men from 18-40.
The "Big Shanty Hotel in the middle bottom is the Lacy Hotel. It was here that the train crew was breakfasting when the General was stolen and the Great Locomotive Chase began. That adds interest when you think there were thousands of Confederate soldiers just across the street from the stolen train.