An extensive range of hills to the east of Mirkwood and north of the Sea of Rhun, source of valuable ores.

In the year TA 2590, after the dragons forced the dwarves from the Grey Mountains, a group led by GrĂ³r, the son of Dain I removed to the Iron Hills and established mines. They prospered and often sent troops to assist other dwarves under attack..

After the Battle of Five Armies, dwarves from the Iron Hills helped to reclaim Erebor, (the Lonely Mountain) and repopulate it.
Encyclopedia entry originally written by PotbellyHairyfoot