Greatest of the Eagles at the time of the War of the Ring. Gwaihir had keen eyesight and was the swiftest of the Great Eagles. He was large and strong enough to carry a grown man. Gwaihir was intelligent and was capable of speech. 

Gwaihir was descended from Thorondor, the greatest Eagle who ever lived. He had a brother named Landroval. They lived in the northern Misty Mountains and had many other Eagles as their vassals. 

In the summer of 3018, Gandalf the Grey asked Radagast the Brown to send word among his friends the birds to learn what they could of the Enemy's plans. The Great Eagles flew far and wide and gathered news of the Nazgul and the mustering of Orcs and Wargs and the escape of Gollum from Mirkwood. 

Gwaihir went to Isengard to bring this news to Gandalf. In the early hours of September 18, he found Gandalf imprisoned by Saruman on the pinnacle of Orthanc. Gwaihir bore Gandalf away, and when the Wizard said that he needed a horse, Gwaihir set him down in the land of Rohan. 

On February 17, 3019, Gwaihir was searching for Gandalf at the request of Galadriel when he found the Wizard atop the Silvertine. Gandalf had vanquished the Balrog in the Battle of the Peak, but the entrance to the Endless Stair had been blocked and he had been unable to escape from the mountaintop. Gwaihir once again bore Gandalf and he found his burden to be as light as a feather, for Gandalf's old life had been burned away and he had been reborn as Gandalf the White. 

The Eagle brought Gandalf to Lothlorien and then at the Wizard's request he flew to seek news of the Fellowship. Aragorn and Legolas both saw him circling above the Emyn Muil. Gwaihir returned to Gandalf with the news that Merry Brandybuck and Pippin Took had been captured by Saruman's Uruk-hai. 

Gwaihir and his brother Landroval led a great company of Eagles to the Battle of the Morannon on March 25, 3019. They swooped in to attack the Winged Nazgul, but the Nazgul fled when Sauron summoned them to fly to Mount Doom where Frodo Baggins stood at the Cracks of Doom with the Ring. After the Ring was destroyed, Mount Doom erupted and Frodo and Sam were stranded on a hill amid flowing lava and falling ash. Gandalf asked Gwaihir to bear him a third and final time. Accompanied by Landroval and Meneldor, Gwaihir raced swiftly to Mount Doom and with his keen sight he spotted the Hobbits through the fumes. The Eagles lifted Frodo and Sam and bore them away to safety. 

Source: www.tuckborough.net
