The Lord of the Rings: Shadow of the East
The mountains of northern Angmar contain the ancient Dwarven city of Zarak Dûm. Its mines are rich in precious ores, and the Ironfist Dwarves who dwelt there prospered. Indeed, they so loved their home that they defied their king when he removed his clan south and east, hoping to reoccupy the abandoned Dwarf-mansion under Cloudy-Head upon the shoes of the Sea of Rhûn.
The complex was never large as Dwarven cities go, for it was too close to Khazad-dûm to become a great gathering place. Instead, it served as one of the many Dwarven outposts, such as those in the Blue Mountains, from which Dwarven craftsman received precious metals and gems. It remained the last holdout of the Ironfist clan in the west before all communication with the city ceased in T.A. 1203. Merchants were puzzled to discover that the great doors had been sealed shut… from the inside.