rooms

This page contains an entry from the official DM Reference.

Areas that are not located on the map are referred to as rooms. When a player enters one, the map goes away and you have something like a text MUD. By default, there would be no way for players to move from one room to another, so you have to handle movement yourself.

You can check the variable area.x to see if a given area is on the map or not.

The following example puts players in a room when they log in and provides a single exit.

Example:

mob/Login()
   if(!loc) Move(locate(/area/birthing_hut))
   return ..()

area/birthing_hut
   Entered(O)
      O << "Waaaaah!  You land in a pile of straw."
      return ..()
   verb/exit()
      if(Move(locate(1,1,1))) //jump to the map or whatever
         usr << "You crawl into the open air..."
      else
         usr << "The hut door is blocked.  You cannot get out."