Hueco Mundo

Hueco Mundo (虚圏 (ウェコムンド), Wekomundo; Spanish for "Hollow World", Japanese for "Hollow Sphere") is the dimension where Hollows and Arrancar usually reside. It lies in between the world of the living and the Soul Society.

Overview
A large portion of Hueco Mundo is covered by a desert, a silent world of death. An unchanging night covers the sky, an endless white desert covers the ground. The tree-like objects are not plants, but rather quartz-like minerals.

Hueco Mundo as it originally appeared, with a black and white sky. It was a different area, where Grand Fisher apparently frequented. The landscape of Hueco Mundo is a seemingly never-ending white desert, with a multitude of dunes. The desert is littered with what appear to be boulders and shriveled trees, but these are actually a form of quartz. In Hueco Mundo, the moon is on the opposite lunar phase of that in the Human World. The vast desert also seems to lack any bodies of water and contains rocky formations. Like in Soul Society, the atmosphere is filled with a high concentration of Reishi, thus allowing smaller Hollows to gain nourishment despite the lack of Human souls. Similar to the case of real world deserts, active life in Hueco Mundo appears to be few and far between. Hollows generally seem to dwell below the surface or in other areas until something provokes them to leave their shelter, like the intrusion of a foreign entity. According to the Shinigami, all Hollows dwell in Hueco Mundo regardless of their shape, size, or power.

Accessing Hueco Mundo
Hueco Mundo is located between the Human world and Soul Society, though it is separated from the bordering dimension known as Dangai. It can only be accessed via Garganta, which tears the dimensional fabric separating the worlds, allowing Hollows to travel to any other dimension at will.