Domumigni

The Elemental Plane of Fire, also known as Domumigni, is one of the least hospitable of the Planes for mortals to tread upon. Unlike Hades whose hellfires serve as dungeon decor for the souls of the damned, the flames of Domumigni shower, course and swell upon this Plane in the same way that rain, rivers and oceans do upon our prime material world. The solid core of Domumigni is comprised of obsidian, volcanic rock and other fireproof minerals but the majority of the Plane is a mixture of molten rock and lava. The extreme heat of Domumigni creates toxic weather as metals and minerals are constantly smelted down and then cooled back into a solid state. Likewise, the mountains of Domumigni are in constant eruption and spew columns of black sulfur and furnace soot into the atmosphere in addition to blazing flakes of lava and embers.
The City of Brass -- Travelers of the inner Planes will inevitably find themselves in the City of Brass. It is the largest city in the multiverse and as the saying goes, anything your heart desires can be found within its golden walls if you are willing to trade all your heart for it. The City of Brass lies at the center of a desert of black sand. Those who travel to the city are protected from the heat of Domumigni by the will and magic of the Efreeti who rule the city. Travelers from nearly every Plane in the multiverse arrive at the City of Brass for its markets and its luxuries. Anything and everything is for sale here, though nothing is as valuable as the slaves of other dimensions (something mortals should be careful to not become if they decide to browse the markets after dark). Gold and silver does not weigh as heavily in the City of Brass as it does in the prime material world, instead most denizens trade for rare stones or magical reagents that are more difficult to acquire in their own dimensions.