Random dungeon generator.
One. Find a map. Or an image of a place. Or a not-place which means or indexes a place.
Two. Go here.
Three. Drag an image into the image search. When the search results come up, search for 'visually similar.' Look for whatever is cool.
Four. Save image and assign it to a place on the map. If you need to write something down to figure out what it means, do so.
Using the previously saved image, repeat steps (skipping insufficiently distinct search results) until you have enough stuff to feel like the map is full.