The Underearth

That what lurks beneath the surface

Unknown to many people above ground, far beneath the surface lies a whole new world.

— Ernist Vonleu

Dun Erôth, also known as the Underearth, is a subterranean landscape, made up of different huge cave systems, that spans across the world. Just like the various continents above ground, not all cave systems are connected, making it just as vast and different as the world above the surface.

Geography

The Underearth can be divided into two layers, both having their own characteristics. Generally the two layers don't intereact with each other.

The Middle

The Middle is what most people refer to if they talk about the Underearth as this is the region that has been explored and studied the most. It encompasses the first twenty kilometers underneath the surface and is comprised of various big cave networks that are connected to both the surface and the Depths.

Topography

This layer holds vast underground caverns and tunnels that can span the same area as a country or continent. Not all cave systems are connected with each other and require a trip through the surface or the Depths to go from one system to the next. Within the different cave networks a variety of biomes and ecosystems can be found and often various biomes are found within one system. This is also the layer that holds many large Underearth cities.

Inhabitants

The most known inhabitants of the Underearth are drow, duergar and svirfneblin, also known as dark elves, dark dwarves and deep gnomes. While the surface counterpart often mixes with each other within communities, the Underearth varient often keeps to their own cities and territories.
Other inhabitants of the Middle include, but are not limited to, Derro, illithits, Grimlocks, Kobolds and Kuo-Toa. Besides these, the Middle is also home to a variety of monsters such as: earth elementals, oozes, spiders, weblurkers and a variaty of aberations.

The Depths

The Depths are located beneath the Middle and is an almost unexplored region as it's known to be the most dangerous. Often Middle inhabitants prefer to travel over the surface if they need to go to another system than to go via the Depths.

Topography

Whereas the caves in the Middle often hold different biomes in one system, the caves in the Depths always contain only one biome. The caves in the Depths are less of a cave or tunnel system and are generally bigger than the ones in the Middle. The Depths also hold various portals to other planes, such as different elemental planes and the Abyss.

Inhabitants

Because most of the Depths are unexplored and the ones that are known are not often traveled, it's unclear who the common inhabitants of these cave systems are.

Type

Underground / Subterranean

Naming

The name Dun Erôth was given to the sprawling cave system by the dwarves of Rasvich. Dun Erôth translates to underground earth in the common tongue, which scholars later shortened to Underearth. The name Underearth is not used by the denizens themselves as they use the domain names.