Lighter Than Air

This massive hangar was originally part of the Naval Lighter-Than-Air Station Santa Ana. 

This is one of two that rise up behind, and easily dwarf, the Costco in Tustin, CA. Built mostly from Oregon Douglas fir, they are two of the largest free-standing wooden structures in the world. In WWII, they housed blimps - six at a time. They still house (or until a recent roof collapse) an experimental cargo blimp commissioned by the Pentagon and NASA. One of the hangars is used for the storage and repair of commercial blimps. 

Not something we expected to run into on our way to get way too much of whatever it was that we didn't need at Costco, it was a very interesting discovery.

Sources and additional reading:

http://en.m.wikipedia.org/wiki/Marine_Corps_Air_Station_Tustin

http://articles.latimes.com/2013/oct/14/local/la-me-airship-hangars-20131015

http://southland.gizmodo.com/these-massive-wooden-hangars-once-housed-wwii-airships-1604793645

Good pics:

http://www.tustinhistory.com/photos-lta.htm