| Category | Caverns |
| Continent | Straiden |
| Region | Bulâd-Gûla |
| Map | Galush |
In their tireless quest for ores and minerals, the Earthen, and especially their miner genies, constructed numerous Underdark passages beneath the lands of Karnegmoth. Many of these passages lie unused and forgotten, serving as a refuge for escaped slaves or wandering Underdark creatures. These tunnels, built in the name of Rilirthad, are collectively known as the Khan's Passages, honoring the Dao Khan who have ruled Rilirthad.
The principal tunnels fluctuate in width from 20 feet to 40 feet. They are interlinked across numerous levels with smaller corridors. The central axis originates at Tachylyte and then radiates outward in concentric rings, connecting all of Rilirthad's significant possessions.
In the Dao Civil War, the Khans's Passages were a labyrinthine network of tunnels where many became disoriented. This subterranean realm also witnessed intense combat, leaving the solidified remains of fallen dao scattered throughout the region.
The subterranean trade routes of Khans's Passages serve as vital conduits for the Rilirthad and the inhabitants of the Underdark. Along the primary trade lanes, the dao charge tolls, with the revenue potentially funneling back to the empire or supporting local Earthen gangs. For many, discerning the difference between those truly serving the empire and those merely posturing as such is a challenging task, rendering the contest of such tolls inadvisable.