That’s the old Air Force Plant 3 in Tulsa, the roof is still covered in grass to help hide it from enemy bombers.
Former Air Force Plant 3 | The Center for Land Use Interpretation
At the southeast corner of the Tulsa International Airport is a former aircraft plant once known as Air Force Plant 3, with a ¾ of a mile-long main building. During World War II, it was a production plant for Douglas aircraft bombers, and after the war it was reactivated to make B-47s and B-66s...
