At an elevation of 4,334 m (14,219 ft) above sea level, Qamdo Airport was formerly the highest airport in the world. It was surpassed by Daocheng Yading Airport, with an elevation of 4,411 m (14,472 ft), on 16 September 2013. It still has the longest publicly used paved runway in the world, at 5.5 km (3.4 mi), a necessary feature due to the reduction in engine and lift performance that aircraft are subject to at altitude, requiring higher than normal lift-off speeds and therefore longer take-off (and landing) runs.

The airport is 2.5 hours by mountain road from the county seat of Qamdo. The long commute is the result of no flat land closer to the city being available to construct an airport.

Visitors are warned before landing to move slowly on leaving the plane and that they may feel light headed or dizzy because of the thin air.

Due to high attitude weather and geologic problems, the airport decided to repair the runway in 2007 and 2013. In October 2015, the construction of a 4000-meter-long second runway started, and it will be in service before 2018.

More Info: en.wikipedia.org