|Location||East of Erebor, northwest of Rhûn|
|Realms||The Kingdom of Durin's folk|
|Description||Hill-remnants of the Ered Engrin and a realm of many of Durin's folk|
The Hills were mined for thousands of years by the Dwarves, being their main supply of iron. The Dwarf-road of Mirkwood ran northeast to the Hills for the Dwarf-traders that went to and from Khazad-dûm and the Hills.
In T.A. 2570 Dragons began afflicting the dwarves in the north and in T.A. 2589 Dáin I was slain by a dragon in the Grey Mountains.Cite error: Closing </ref> missing for <ref> tag Over hundreds of years it became a great realm, especially after the destruction of Erebor in T.A. 2770.Cite error: Closing </ref> missing for <ref> tag
Before the death of Smaug in T.A. 2941, the dwarves' realm in the Iron Hills was the main dwelling of Durin's folk in the East, and also the strongest realm militarily in Wilderland. After Smaug's death Dáin Ironfoot became King under the Mountain; how many dwarves may have returned to or stayed in the Iron Hills after the Battle of Five Armies is unknown.