While there exist some realms which function as something similar to an ‘hell’ of sort, no one has ever found the Christian hell. What they HAVE found, however, is The Inferno. The Inferno is realm of pain and madness which exist within the Border in no specific location. Instead it is accessed in the Border through places of corruption, pain and other negative emotions.
Named after Dante’s Inferno (part of the Divine Comedy), this is a realm primarily inhabited by demons (especially the incorporeal or semi-corporeal type, although they can be fully corporeal within that realms) but also other horrific which would have business there. Indeed, the Inferno can act as something of a ‘shady neighborhood’ of the cosmos for spiritual being. Mortals (and semi-mortals) rarely enter the Inferno due to its nature being inimical to human nature, not to mention how nightmarish the place is to the mortal mind combined with the evil nature of its inhabitants.