Capital region of Japan.
If you are looking for fun day trips in Tokyo, you might want to pick up the "Tokyo and Yokohama Guide" (free!) at the Tsukuba Information Center. The guide is produced by Metropolis and is about 60 pages long. It gives you ideas about what you can find in the various areas of Tokyo and Yokohama, and also about the shopping, dining, and nightlife options in each area.
And, while you are at the Tsukuba Information Center, you can also pick up the latest editions of Metropolis magazine, which is a weekly treasure trove of information about what is happening in the Tokyo area.
Getting to Tokyo