Cavern of Rest

The Cavern of Rest was the divine realm of Marthammor Duin. It was located in Nidavellir, the subterranean third layer of Ysgard according to the Great Wheel cosmology, and in Dwarfhome according to the World Tree cosmology.

Cosmography
From the Great Wheel perspective, the Cavern of Rest was located among the ever-shifting tunnels of Nidavellir.

In the World Tree, the Cavern was located in a remote part of Dwarfhome's foothills. Despite its secluded location, other deities' domains could be accessed from there.

Inhabitants
The Cavern was inhabited and guarded by dwarf petitioners who in life had traveled to the surface of the world and had died above ground. The realm was also guarded by boars and war dogs trained by Marthammor Duin.

Marthammor himself did not spend much time in his realm, but instead traveled in north Faerûn in his avatar form.