Yanggu (G-404) Airport, identified by ICAO code RK13, is a military airfield located in Yanggu County, Gangwon Province, South Korea. It operates under the authority of the Republic of Korea Army and is not open to scheduled commercial air traffic. The facility is situated in a mountainous region near the Demilitarized Zone (DMZ), making it strategically significant for military operations and logistics in the area. No IATA code has been assigned, reflecting its non-commercial status. As a restricted military installation, public information regarding its infrastructure, operational capacity, and history is limited. The airfield primarily supports rotary-wing and light fixed-wing military aircraft operations in the region.