It is virtually unknown, as are all N. Korean (DPRK) airbases. Hyesan Airfield is an airport near Hyesan, Ryanggang-do, North Korea. It is sited near the northern border with China. The facility was extensively improved in 1971, and there may have been further plans to pave the airfield, based on the continued presence of construction vehicles. It is apparently a unpaved and utilitarian airstrip that may have had concrete at one time that is now mostly reclaimed by nature.