Carl Jung would argue that the "Devil's Doorway" is an archetype. Humans need to compartmentalize evil. We cannot accept that evil exists everywhere, so we create specific points of entry —a doorway in a church, a cleft in a rock, a basement door that sticks.
Unlike the church doors, which are sealed shut, this natural "Devil’s Doorway" is perpetually open. Occultists believe it is a thin place —a location where the veil between the living and the dead is worn thin enough to walk through. The Devil-s Doorway