Gnoll Mountain is a landmark near the top of the Jerall Mountains. From there, you'll have breathtaking views of Cyrodiil, and on good days, can see Bruma to the west, Imperial City to the southwest, and Cheydinhal to the southeast in one panoramic view.
There's a small campfire with bed, plus some food (venison, mutton, lettuce, etc.) and the only Grey Robe Hood along with the Grey Robe inside the tent. It's a great place to vacation in the mountains when on a break from saving the people of Cyrodiil.
You will visit Gnoll Mountain as part of one of the Dark Brotherhood quest, The Coldest Sleep, where you are required to kill a nord named Havilstein Hoar-Blood, who resides there along with his pet wolf.