I have a large " strategic map of central europe" made by the U.S. War Department in 1915-can't find any info

It also states " showing the international frontiers" It was made by the WAR COLLEGE DIVISION, GENERAL STAFF. I don't know really anything about maps. I don't know what all the information on it means & I've tried reasearching it, but can't find anything on it. It is obviously from World War I. It's a large wall map measuring 6' x5'. Is it valuable? It's in somewhat poor condition & I have it for sale on ebay now because I can't afford to have it restored, but I figure someone else can. ANY INFO AT ALL WOULD HELP!! THANKS!