https:// en.wikipedia.org/wiki/Northwest_Angle_Airport
>Northwest Angle Airport covers an area of 18 acres which contains a runway designated 8/26 with a 2,380 x 105 ft (715 x 32 m) turf surface. For the 12-month period ending August 3, 1979, the airport had 400 aircraft operations, an average of 33 per month: 100% general aviation. At that time there weren't any aircraft based at this airport.