The People of the pocket realm of Brocschtal are simple folk who live as they have for thousands of years. Farming the land, raising sheep, getting in the occasional brawl. And fighting off the infernal attacks of ghouls.
You come upon a ruined building in the back section of a city park (or other out of the way area of the city). The ruins are fairly overgrown. All that is really standing is a doorway and its frame. If you pass through the opened door, you travel to a different world. If the door closes, there may not be a doorway back to get you back.