The Naval Air Station at Lakehurst, in the middle of New Jersey, was the historic center for lighter-than-air aircraft activity in the USA. It is now part of a combined Navy, Army, and Air Force base called Joint Base McGuire-Dix-Lakehurst, and is still a major testing and training center for aircraft carrier flight operations, such as catapult launching and landing arresting systems. The Lakehurst portion, now a Naval Air Warfare Center, has six blimp hangars, the largest collection in the nation. Hangars 5 and 6 are adjacent to one another. They were completed in 1943, and resemble the other fifteen or so new blimp hangars erected at blimp bases that were established quickly to defend naval and shipping fleets during WWII. They are used for non-blimp-related engineering and storage now. Hangar 2, located adjacent to Hangar 1, was the first WWII hangar to be constructed in the US, finished in 1942 to house blimp maintenance and refitting operations. Hangar 3, next to it, was a training blimp hangar, finished soon afterwards. Today they are used as machine shops and a gymnasium for the officers on base. Hangar 4 was a WWI-era blimp and balloon hangar, originally located on a base in Norfolk, Virginia. It was moved to Lakehurst in 1931. Though it is called Hangar 4, it was the second blimp hangar on base. It is now cut off from the flight line, and is used for storage by FEMA and state emergency agencies. The largest, Hangar 1, was the first large blimp hangar in the USA. It was built in 1921 to construct the USS Shenandoah, the largest American-made airship at the time.