The post’s first library occupied a small space at the back of the Signal Corps office, but in 1888-89 the military spent $1,409.13 to build a one-story, brick, hipped-roof library with multiple wings. A visiting Helena reporter called the structure “not especially artistic without, but very comfortable within.” Between 1892 and 1911 the library also served as a post office, receiving mail by stagecoach from Fort Benton three times a week and providing a tangible connection to family and friends. Together with the chapel/school, it supported officers’ efforts to encourage, and later require, unschooled enlisted men to attend classes and visit the library after work. Officers also used the library to study military manuals as they improved their training through a program coordinated by Fort Leavenworth. The library carried thirty-three newspapers and fifteen magazines, and officers transferred from the fort typically donated books and even furniture, helping the collection grow to more than a thousand volumes. Checkers and chess sets were available as well. In 1941, the building’s interior was completely remodeled, removing all signs of its former use.