Ulaanbaatar Chinggis Khaan International Airport — Ulaanbaatar (Sergelen), Mongolia

Mongolia's principal air gateway, Chinggis Khaan International Airport, retains the historic code UBN even after relocating in 2021 to a new site in Sergelen sum within Töv Province, several dozen kilometers south of the capital. The move replaced the older, more cramped Ulaanbaatar airport that sat within the city itself and had grown constrained by surrounding terrain and urban expansion. The facility takes its name from Chinggis Khaan, the thirteenth-century founder of the Mongol Empire, and was built with a considerably larger runway and terminal capable of handling wide-body aircraft the previous site could not accommodate. MIAT Mongolian Airlines operates its primary hub here, connecting Ulaanbaatar to cities across East Asia, Europe, and beyond, while the airport also supports the country's expanding mining, tourism, and business travel sectors that have driven demand for greater capacity.