Yesterday, Anna and I wondered what is the largest airport in the world. It turned out the question is ambiguous and has to be re-phrased more accurately.
  • What is the largest airport by land area: King Khalid International Airport in Riyadh, Saudi Arabia, 17 times larger in area than London's Heathrow, though much, much less busy.
  • What is the largest airport terminal building in the world: That would be Hong Kong's airport international terminal. Curiously, it appears that the new terminal opened in Beijing just last week is much larger. It's not officially on the charts yet.
  • What is the busiest airport in the world: Atlanta's airport handles 75 million passengers yearly.
By the way, in a related question of the world's largest airline, the Americans have a clear lead. By the amount of passengers handled yearly, 5 American airlines (Southwest, American, Delta, United, Northwest) lead the list. Of the non-American airlines, Lufthansa is the largest (carrying about half as much passengers as Southwest). Fleet size-wise, American Airlines leads the flock with 653 planes (compare this to El Al's 37...)