I have never run a dungeon crawl before, such as the one linked [here](http://gibletblizzard.blogspot.sg/2011/11/dungeonfu.html). How do you tell the players what they see? Some examples from older ROG books I have have description in the form of "You come to a passageway, 5 feet wide and extending about 30 feet long, before it ends at a wall with a door set in it" but some of the shapes of the rooms defy simple description. 

What sort of visual aids or techniques can I use to 1) show the layout of each passageway and room and 2) run combat inside a dungeon crawl where players can virtually "go anywhere?". I'm using 13th Age, which does not use a grid but measure distances with abstract range bands. But this is just for context, it is not a 13th Age question.