Board Thread:Suggestions forum/@comment-27831234-20160911184721/@comment-26486187-20160913072620

They did find out how to mass produce metal, as seen in the great forges of Erebor. They were also incredible building engineers, as seen in practicaly all places that the Dwarves lived in. It has to be a pretty advanced peoples to be able to make such huge halls without them caving in.