Cheongju International Airport/Cheongju Air Base (K-59/G-513) — Cheongju, South Korea

Fighter jets and airliners share the same tarmac at CJJ, a joint civil-military facility that doubles as an active Republic of Korea Air Force base while also serving as North Chungcheong Province's principal civilian gateway. Cheongju's airport handles a mix of domestic routes connecting to Jeju Island, along with a modest slate of international service toward Chinese cities that has fluctuated over the years alongside broader diplomatic and travel trends between the two countries. Compared with Seoul's Incheon and Gimpo airports a couple hours north, Cheongju offers a quieter, less congested alternative for residents of the central Chungcheong region, sparing them a longer overland trip for many domestic itineraries. The airport has occasionally been floated as a secondary hub to relieve pressure on the greater Seoul metropolitan airports, given its comparatively young infrastructure and available capacity. Low-cost carriers have expanded their presence here in recent years, adding competitive pricing pressure that has gradually boosted passenger volumes beyond what the airport historically handled as a smaller regional field serving a military-first mission.