One of the most important railroad lines in Tokyo is “Yamanote line” that encircles the central part of Tokyo. Trains on inner circle rails run counterclockwise, and trains on outer circle rails run clockwise.
“Yamanote line” is important because many major terminal stations on it, and various railroad lines and subway lines connect with stations on “Yamanote line”.
Take the lines from the airports for example, Skyliner and Keisei Main Line Limited Express from Narita International Airport connect with Nippori station of “Yamanote line”. N’EX and Rapid Train from Narita International Airport connect with Tōkyō and other stations of “Yamanote line”.
Monorail from Haneda Airport connects with Hamamatsucho station. Keikyū Line from Haneda Airport connects with Shinagawa station of “Yamanote line”.
Basic structure of railroads network
JR (Japan Railway) East runs many lines. “Chūō – Sōbu Line” runs across the middle of “Yamanote line” circle. “Chūō – Sōbu Line” runs through Shinjyuku station and “Sōbu Line” goes through Akihabara station, “Chūō Line” goes through Kanda station and ends at Tōkyō station. Other various JR East lines connect with stations of “Yamanote line”.
Bullet trains’ (Shinkansen’s) terminal station is Tōkyō. Tōhoku, Yamagata, Akita, Jyōetsu, Hokuriku, Tōkaidō Shinkansen leave and arrive at Tōkyō station. But JR Tōkai runs Tōkaidō Shinkansen.
Various company’s railroads and subways connect major terminal stations of “Yamanote line”. Examples of such major terminal stations are Ikebukuro, Shinjyuku, Shibiya, Shinagawa, Shimbashi, Tōkyō, Ueno stations etc.
Take Shinjyuku station for example, besides various lines of JR East, the following lines connect with Shinjyuku station. Keiō Line (Keio Corporation). Odakyū Line (Odakyu Electric Railway). Subway lines connect with Shinjuku stations are following. Marunouchi Line (Tokyo Metro). Ōedo Line (Toei Transportation). Shinjyuku Line (Toei Transportation).
In the case of Shibuya station, the following lines connect with Shibuya station. Den-entoshi Line (Tokyu Corporation). Tōyoko Line (Tokyu Corporation). Inokashira Line (Keio Corporation). Subway lines of Tokyo Metro are following. Ginza Line. Hanzōmon Line. Fukutoshin Line.
The network of railroads and subways
Thus, the network of railroads and subways in Tokyo is very complicated.
In above picture, solid bold colored lines represent subways, black and white line and grey lines represent JR lines, other lines represent other company’s lines.
You need the app for moving around Tokyo
As the network of railroads and subways in Tokyo is very complicated, I recommend downloading and installing the app called “Japan Travel – transit, taxi” (for iOS), “Japan Travel – Route, Map, Guide, JR, taxi, Wi-Fi” (for Android) from App store or Play store.
From the menu, select “Route Search”, you type in the departure place and destination or tap them on the map (to show map, you tap “OPEN MAP” for iPhone, “Search by Route Map” for Android phone), and designate leaving time, then the app shows you several routes (including station name of changing the trains) with train or subway departure and arrival time.
You can read “How to use Japan Travel app” in this site.