Otemachi station yard map, Tokyo Metro
When I was in Japan, I took the Tokyo Metro-Chiyoda Line and went to the office. My exit station was Otemachi, which is one of the largest stations in the subway system.
Look at the top figure. It’s the station yard map of Otemachi illustrated by Tokyo Metro. I got off at the Chiyoda Line platform (C11) on the extreme left in the figure. Then, I walked up and down; right and left from the subsurface to exit number B7, which is shown on the extreme right in the illustration. It’s about 700 m from the platform to the exit and around a 10 minute walk; however, the entire walk is still located within the same station yard. What a labyrinthine station it is!
You can see another complicated example in the bottom figure. It’s famous "Shibuya Dungeon", where 3 subway lines extend into it. If you would like to transfer from the Fukutoshin Line (F16) to the Ginza Line (G01), you should take a trip from the fifth basement to the third floor. So you should climb seven flights of stairs or escalators!
Why are these so complicated? It’s probably because of their long histories. For example, in Shibuya Station, the Ginza Line (G01) was constructed in 1938. Meanwhile the Fukutoshin Line was completed in 2008, a 70 year difference. When they constructed the Ginza Line, no one could imagine the future of the city.
Otemachi and Shibuya stations… are these labyrinths or dungeons in the Tokyo Metropolitan area?
Shibuya station yard map, Tokyo Metro
Otemachi station yard map, Tokyo Metro (in Japanese):
Shibuya station yard map, Tokyo Metro (in Japanese): http://www.tokyometro.jp/station/shibuya/yardmap/index.html