Mount Gundabad is a mountain at the northern end of the Misty Mountains.
According to the Dwarves, Durin the Deathless, oldest of the Fathers of the Dwarves, awoke at Mount Gundabad in the north of the Misty Mountains shortly after the Awakening of the Elves. Mount Gundabad remained a sacred place to the Dwarves ever after.
In the Third Age, the Orcs of Angmar claimed it as their capital, which was one of the reasons for the Dwarves' special hatred of this people. After the fall of Angmar Gundabad remained an Orc stronghold, until it was cleaned of Orcs during the War of the Dwarves and Orcs. But it is likely that the Orcs repopulated it over the next two hundred years, although there probably weren't as many.