Reins of the Winterspring Frostsaber

Reins of the Winterspring Frostsaber summons a unique frostsaber mount that is not wearing any armor. It is the only (Alliance) epic mount that can be used with the novice riding skill; however, players must still be level 40 to use the mount.

Source
This mount is rewarded from the quest Quest:They Grow Up So Fast (Alliance). The mission will take at least 20 days, but those devoted enough will get the mount with no trouble.

It was once sold by Rivern Frostwind on Frostsaber Rock in Winterspring for. You had to be with the Wintersaber Trainers to purchase this mount.