oubliette

An oubliette is a type of dungeon, traditionally described as a subterranean chamber into which a prisoner is lowered and from which there is no practical means of escape other than exit through the same opening by which the prisoner was admitted. The word comes from the French oublier, meaning “to forget,” and the idea conveys the intention that the inmate would be forgotten or left to languish.

Construction and features commonly associated with oubliettes include a vertical shaft or well-like pit with a small doorway or trapdoor at the top. Access is typically through a single ceiling opening, often with a grate or only a narrow opening that prevents obstacle-free ascent. The room below is usually bare, with little or no furnishing, designed to be inhospitable and easily overlooked by guards and observers.

Historical use and interpretation are debated among scholars. While castles and fortifications did house prisoners in dungeons, the distinct architectural form of a true oubliette—an isolated, forget-meant confinement accessible only by a single top access—appears infrequently in surviving medieval evidence. The term has also been applied more broadly in popular culture to describe any deep, inaccessible prison pit, leading to cinematic and literary associations that reinforce the oubliette as a symbol of cruel, clandestine imprisonment.

In cultural contexts, oubliettes appear as motifs in Gothic fiction and fantasy, where they function as narrative devices to evoke danger, secrecy, and punishment. They are often contrasted with ordinary dungeon spaces to emphasize isolation and neglect.