Naval Air Warfare Center, Pennsylvania

Officially closed in 2001, this was an aviation R&D center north of Philadelphia, operated by the Navy, employing over 1,000 people. Included the Naval Command Control and Oceanic Surveillance Center. Many of the functions of the installation were relocated to Patuxent Naval Air Station, and to Navy facilities in San Diego. The runway of the airfield has been covered in housing and an office park, though the largest building, the former Brewster Aircraft plant, is still there, and is being leased.