Large train stations in Japan often have a lot of shops and restaurants inside. Tokyo Station, the terminal of 'Shinkansen' or 'bullet trains', has 120 shops inside ticket gates and 80 outside. They make up a massive shopping and gourmet district named 'Tokyo Station City'. Their main staples are 'bento' or 'lunch boxes' which you can enjoy on a long-distance train. A good bento would make your trip more enjoyable. You might wander in the city like a huge labyrinth(*) when you go into there without a map. But at least you don't have to worry about starving or freezing to death as long as you have enough Japanese yen. They serve and sell various things you could be in need for while wandering. Of course you can also use them on a train, or after getting off the train. *Note: The challenge level of Tokyo Station as a station labyrinth is beginner level. The most challenging station in Tokyo is Shinjuku Station. Here is the video about the station. Check also this! http://youtu.be/7AKQzxl1Ick - Shot in 1080p full HD with an iPhone 4S on Jun. 20th, 2012