College Park Airport is the oldest continuously operating airport in the world. Its story began in 1909, when Wilbur Wright taught two U.S. Army officers how to fly there. The Army chose the site for its large, open, level ground, lack of buildings, and closeness to the Baltimore & Ohio railroad tracks, which made it easy to move people and equipment between Washington, D.C. and College Park. Throughout the early 20th century, start-up businesses and government agencies carried out numerous aviation experiments and innovations there, giving the field the nickname Field of Firsts because of the significant aviation firsts that occurred there. The historic airmail hangar on the field dates to 1919.