Hangar No. 2

Hangar No. 2 (Building 29) at the former Marine Corps Air Station in Tustin, California measures 1,072 feet (327 m) long by 292 feet (89 m) wide by 192 feet (59 m) tall. 
It and its "sister" structure Hangar No 1 - (partially visible to the right) are listed on the National Register of Historic Places and designated National Historic Civil Engineering Landmarks. 

The two hangars, built in 1942 of Oregon Douglas fir, are among the largest freestanding wooden structures in the world. While its sister structure (the North Hangar) is slated to be included in a new park, the future of this hangar is uncertain.^[1]

<sup>Have personally been to this facility in Santa Anna Calif... 

It is truly a very large building!</sup>