All very nice but you are all wrong ... do some research first
Qamdo Bangda Airport (ZUBD) located in Bangda, Tibet, is not only one of the [url]highest[/url] airport in the world (altitude: 14219 ft.) but at 18045 feet, runway 14/32 is the longest public use runway in the world.
Well done, Harold 8-)
I mentioned Amarillo International because I've lived there and have the number 13,502 (runway length) still buzzing in my head




