The CIA's black sites were unsurprisingly scary as hell. According to the just-released Senate report on the CIA's torture program, one detention center was basically a medieval "dungeon" — and that's in the words of the site's "chief of interrogations."
CIA detainees at the COBALT detention facility were kept in complete darkness and constantly shackled in isolated cells with loud noise or music and only a bucket to use for human waste. Lack of heat at the facility likely contributed to the death of a detainee. The chief of interrogations described COBALT as a "dungeon." Another senior CIA officer stated COBALT was itself an enhanced interrogation technique. [Senate Report]