Tribhuvan International Airport (Nepali: त्रिभुवन अन्तर्राष्ट्रिय विमानस्थल) (IATA: KTM, ICAO: VNKT, colloquially referred to as TIA) is an international airport located in Kathmandu, Bagmati, Nepal. It has a tabletop runway, a domestic terminal and an international terminal. As the country's main international airport, it connects Nepal to over 40 destinations in 17 countries. The airport is designed in a shape of an airplane when looked from above. The runway extending from the nose to the tail, with the terminal buildings aligned along the fuselage. The distinct shape is visible after takeoff, and while hovering.

The airport is a hub for two international airlines, the flag carrier Nepal Airlines and Himalaya Airlines, along with multiple domestic carriers. The airport is considered as a starting point for Mount Everest international tourists, with several daily flights to Lukla. Several airlines also offer Everest sightseeing flights from Kathmandu.

Due to heavy traffic congestion, winter fog and the airport running out of its full capacity, the Government of Nepal promoted Gautam Buddha International Airport and Pokhara International Airport as alternative airports in case of necessary diversions.