Third Fleet shipwrecks

The Third Fleet shipwrecks are located in the Great Sea, between the Eastern Kingdoms and Zandalar. These ships were part of the Kul Tiran Third Fleet during the Second War, when they were destroyed by the Old Horde's red dragons. The Horde sailed there during the Fourth War with the Banshee's Wail and the Crimson Squall, and sent people to retrieve Marshal M. Valentine's body from the sea floor. They were discovered by Wildhammer gryphon riders hunting for Blood Prince Dreven and attacked.

More of the fleet can be found shipwrecked in the Wetlands.

Shipwrecks

 * Fathomdasher
 * Songswallow
 * Gale's Reprieve
 * Drustvaria
 * Pride of Tiragarde

Speculation
The reason that part of the fleet wound up in the Wetlands while another part was found in the Great Sea is likely that ocean currents moved them apart.