NASA's Ames Research Center is home to the largest wind tunnel in the world, the National Full-Scale Aerodynamics Complex. The test section measures 80 ft. x 100 ft. (24 m x 31 m). This is just one of the many wind tunnels located at Ames.
Scientific - Wind Tunnels
Note the dirigible hanger to the west and the other two large hangers on the other size of the runways.