Nihonbashi is one of recommended areas to visit in Tokyo. This place has many shops and architecture to see. It’s close to Ginza, so I would recommend to walk through from Ginze to Nihonbashi, or vice versa. Marunouchi, another famous area in Tokyo, is like between Nihonbashi and Ginza but on the other side of Japan Railway track. Marunouchi can be also reached by walking.