Throne of the Four Winds is a raid in the Skywall complex introduced in World of Warcraft: Cataclysm. It can be found off the southwest coast of Uldum at [38, 81] high in the air.
This dungeon, along with Bastion of Twilightand Blackwing Descent, is meant to an entry level raiding instance, much as "Naxxramas" was for Wrath of the Lich King or Karazhan was for Burning Crusade. 
The final boss of the raid instance (Al'Akir, does also have a low chance to drop the mount Reins of the Drake of the South Wind. The mount has the same chance to drop on all difficulties.
Skywall (Uldum) [38, 81]
With Deathwing's return, Al'Akir is once again free to walk the winds of Azeroth. He has become one of the Destroyer's staunchest and most powerful allies, and called the Conclave of the Four Winds, ancient wind elementals nearly as powerful as Al'Akir himself, to aid in the elemental invasion of his former home.
Al'Akir's temperament is that of the sky: calm one moment, and furious the next. But some few aspects of the Windlord can be said to be consistent. He possesses godlike power that will buffet and shake Azeroth if left unchecked - and he will not allow himself to be chained again.
Al'Akir the Windlord's personal lair, the Throne of the Four Winds, glides high among Skywall's boundless vistas. Now that the barriers of the Elemental Plane have been ruptured, Al'Akir is free to travel Azeroth's winds at his leisure. He has mustered his fiercest tempests to scour Uldum of life and seize control of the mysterious titan-forged Halls of Origination.