Tronjheim was the capital city of the dwarves, located within Farthen Dûr. It is a city-mountain and took generations to build. "Tronjheim" meant "Helm of Giants" in the Dwarvish language. Despite complaints that it was a drain on dwarven resources, it was always kept garrisoned and ready for use. Orik stated that in times of misfortune it was capable of housing the entire nation of dwarves. In the three times it had been needed for this, it saved the entire dwarf race from destruction. Its construction was that of a mile high cone, capped by the Star Sapphire and the Dragonhold. At the gates stood two giant statues of griffins.
"Trondheim" is the name of one of Norway's oldest cities: it was the capital of Norway until 1217 AD. The name "Trondheim" means "home of the throne" in Norwegian (Trond = throne, heim = home).