Another door option that would be helpful is just a “Walled-Off Stone Door. ”
This would be really helpful for games like Heroquest where you want some of the “Fog of War” effect of dungeon exploring to not always bring you to an actual door within an archway. What you find is a dead end, or a sealed off door.
This might also create some interesting possibilities for secret doors or excavation. Some THING was trapped behind this wall for a reason. Do you dare you dig it out to find out?