Hell

Hell is the term used across many religious and mystical traditions for a realm of suffering, punishment, or exile — variously described as the destination of the wicked after death, the abode of demons and other malevolent beings, and (in some traditions) a temporary state through which souls pass on their way to purification. The specific character of Hell varies enormously across the traditions that describe it: the Christian Hell, the Islamic Jahannam, the Jewish Sheol and later Gehenna, the Buddhist and Hindu Narakas, the Chinese Diyu, the Japanese Jigoku, the Aztec Mictlan, the Norse Hel, and many others.

The imagery of Christian Hell — subterranean, fiery, populated by devils — was extensively elaborated in medieval and early-modern literature (Dante's Inferno, Milton's Paradise Lost), but the New Testament itself gives comparatively little detail. Older Hebrew Sheol was closer to the Homeric Hades: a shadowy, undifferentiated afterlife shared by all the dead. The Buddhist and Hindu Narakas are elaborate systems of many hells, each with its specific torments and specific karmic causes — but importantly, all impermanent: even the deepest hell is a temporary station in the cycle of rebirth, not eternal damnation.

Comparative mythology treats Hell as one aspect of a broader Underworld archetype — the realm-below, the land of the dead, the mirror-image of the surface world — which every culture with a developed cosmology has mapped. The Greek Hades, the Sumerian Kur, the Egyptian Duat, the Mesopotamian Irkalla: all describe subterranean or interior lands with their own geography, their own rulers, and their own passage-rites for the newly deceased.

In psychedelic experience 'Hell realms' are a widely-reported category — sometimes as brief terrifying passages, sometimes as extended states that experiencers describe using the specific language of their culture's Hell tradition. Contemporary psychedelic-integration literature has produced substantial guidance on working with such experiences constructively: understood as encounters with the psyche's unintegrated material rather than as literal metaphysical events, they have frequently proven to be some of the most therapeutically productive experiences of the whole cycle. The Buddhist and Hindu framing — that even Hell is temporary and that everyone who arrives eventually leaves — is often reported as unexpectedly reassuring in that context.

Sources:
Wikipedia — Hell
Wikipedia — Underworld