Circular airport?
 

http://www.curbed.com/2017/3/24/1504...airport-design

Not sure that a circle would be built but I could see a square. A squareport you might say.

Maybe the circular shape was inspired by the pills these Dutch dudes were high as a kite on.

'diameter of over 2 miles"

OK, I rounded up to 3 and calculated circumference. You have to make a 90 degree turn in about 12,000' at standard runway widths.

Hmmm

Belongs in the TOTD thread...