What bird has the World's longest wingspan?

Royal albatross
  The longest winged of all birds are the albatrosses. The thirteen species of these giant tube-nosed birds are found in the southern oceans, apart from three Pacific species which cross the equator during migration after their breeding season. Mostly, albatrosses ride the winds effortlessly in the zone of the roaring forties, feeding on the abundant fish and plankton of that area and migrating huge distances yearly. Their breeding places are remote islands which are the only dry land that they ever encounter. They are slow-maturing and long-lived. According to some estimates, albatrosses reach ages of as much as seventy years.