Requires a key to enter that is dropped by one of the 2 names wights. You need to enter the Barrow's Gate to find the 3 locations for the Garth Agarwen Exploration deed:
* Garth Agarwen Gate 28.8S, 23.9W
* Ivar's Crypt 28.1S, 23.1W
* Spring of the Red Maid 29.7N, 23.2W