From Wikipedia:
Ulyanovsk Vostochny (Russian: Ульяновск Восточный)(sometimes referred to as Ul'yanovsk or Ulyanovsk Northeast) (IATA: ULY, ICAO: UWLW) is an airport in Russia located 28 km northeast of Ulyanovsk. This runway is the second longest public use runway in the world, after Qamdo Bangda Airport, with a length of 16,405 feet. It is also the widest, with a total width of about 344 feet. Low altitude & handy to Europe.
Qamdo Bangda Airport (IATA: BPX, ICAO: ZUBD) (Chinese: 昌都邦达机场, Tibetan: fill in), located in Bangda, Qamdo, Tibet, is the highest airport in the world, with an altitude of 4,334 metres (14,219 ft). At 5,500 m (18,045 ft), runway 14/32 is the longest public use runway in the world. The low air pressure at this altitude makes a higher takeoff and landing speed necessary, and therefore a longer runway.