
Nikko is a popular daytrip from Tokyo and one of Japan's favourite tourist attractions. The shrines and the temples in the city, and above all the spledid Tosho-gu Shrine are among the best sighst in the country so you should include Nikko in your trip even if you have only one week.
The main attraction is the Tosho-gu shrine. More Chinese than Japanese this building dates back to the 1650s, but was restored in 1818. Other attracions include the Futara-san-jija shrine, the Taiyuin-byo, basically a smaller version of the Tosho-gu, the Shin-Kyo bridge and the Rinno-ji Temple.
A trip to Chuzenji-ko Lake is nice too. Almost an hour by bus along a winding road. Beautiful scenery and a 100 meter high waterfall, well-known for suicides are the main attractions.
Akihabara
Asakusa
Daisetsuzan
Ebisu
Fukuoka
Fukuoka City
Ginza
Hateruma Island
Hiroshima
Iriomote Island
Ishigaki Island
Izumo
Kamakura
Kansai
Kitsuki
Kobe
Kokura
Kyoto
Marunouchi
Mito
Miyako Island
Moji
Nagano
Nagasaki
Nagoya
Naha
Nikko
Osaka
Roppongi
Saitama
Sapporo
Shibuya
Shikoku
Shimonoseki
Shinjuku
Takayama
Taketomi Island
Tobata
Tohoku
Tokashiki Island
Tokyo
Tokyo Odaiba
Ueno
Wakamatsu
Yahata
Yokohama
Yonaguni Island
Zamami Island