Iron Hills

The Iron Hills was a range of hills in the northeast of the known parts of Middle-earth, where a Dwarf-realm was founded by Grór son of Dáin I after the Dwarves were driven from the Grey Mountains by the Cold-drakes.

The Iron Hills was the main dwelling of Durin' folk in the East, and wa also the strongest kingdom in Wilderland before the death of Smaug

The Dwarves of the Iron Hills were known for making a flexible iron armor from of course, the rich iron supply in the hills.