EAA AirVenture Oshkosh (formerly the EAA Annual Convention and Fly-In) is an annual gathering of aviation enthusiasts held each summer at Wittman Regional Airport   in Oshkosh, Wisconsin, United States. The airshow is sponsored by the Experimental Aircraft Association (EAA), an international organization based in Oshkosh, and is the largest of its kind in the world. The show lasts a week, usually beginning on the last Monday in July. During the gathering, the airport's control tower is the busiest in the world.