I hope someone can answer a few questions for me. CURRENTLY, is it the Tennessee River that divides the state into the 3 grand divisions? Then, is Decatur County considered to be in West TN? When was TN shown on a map as divided into 3 grand divisions? Is it an official designation? I just know someone is either a historian or a teacher on this list and will have the answer. I took TN history in junior high, but that's been a while back. Thank you. Linda