Miradelgûn is a diverse region of forests, grassy plains, swampy canyon valleys, and highlands. It is bordered to the north by Cinazan and west by Grashakh. The south and eastern tracts of the region end at the Sands of Hell. The blistering sands of this desert snake along the south and then up the west.
In the southeastern corner of the region is a bay that was unnaturally formed from the anger of a god. In the Horgon Era, the god Poseidon was angered when a sect of Talos worshipers defeated his storm giant clergy at Hleirim. This anger resulted in the sinking of the city and the flooding of a section of the Sands of Hell. This flood of ocean water resulted in the creation of the bay Klo'nah Lomok. Today, this bay is commercial route for those seeking to reach the ports of the Ogre Union and the dwarven mountain holds of Rethmorg. The ocean winds coming up this bay result in fierce sandstorms and windy conditions in this area of Miradelgûn.
Miradelgûn is largely a wild area with few major settlements. The two largest civilized areas are the lands under control of the Ogre Union and Rethmorg. The Khazarkar Empire and the Orchish Empire have tried to expand into Miradelgûn, but have had little success.
The Underdark region beneath Miradelgûn is Miryeril.