The mines are commonly known as the Deeps, forming a labyrinth of corridors, galleries, pits, and smaller halls on a disturbing number of levels. The miners of Khar Rhûz have created a large part of the Deeps. As a result, most of the ceilings are low—built for dwarven size. Almost all of the entrances are located in Khar Rhûz; a few others are located in Okoros, which is also engaged in mining. The border tunnel on the kaer’s equator serves as a measure for planning the mining. No one dares to dig too close to the wards, to avoid the risk of weakening them. The architectural calculations are done by the Miner’s Guild, which takes great care to avoid another disastrous cave-in.