View from a high point, possibly a building, of sailors in training at Great Lakes Naval Station, near North Chicago, in Lake County, Illinois, in World War 1. They march from closed three column abreast formation into a spread formation for calisthenics. They follow a leader in performing exercises. Closeup of the exercise leader in action on a platform. About 20 sailors running a race, as others watch from sidelines. Teams of sailors playing a type of race passing a basketball under their legs. Large group of sailors boxing in pairs. Two sailors in a boxing match, encircled by other sailors, and refereed by a Marine officer in shirtsleeves. Change of location to Key West, Florida. Brief glimpse of U.S. marines in military combat maneuvers at a sandy area. As they move forward, an explosive charge ignites nearby.