Some places where you can actually learn something about Japan.
Tokyo national meuseum
The Tokyo national museum in Uneo park is one of the largest art museums in the world and is the oldest in Japan. It holds about 110,000 objects including some cultural objects from Asia. It has the biggest Japanese collection in the world. The Gallery Of Horyuji Treasures: This gallery contains buddhist treasures from a temple in Nara which was founded in 607 AD by Prince Shotoku. It has bronze statues and ceremonial masks, and dances.
Adachi museum
This museum in Yasugi, Japan is known for its gardens. It and is usually voted best gardens in Japan every year. It was founded by Adachi Zenko and has about 100 paintings by the artist Yokoyama Taikan. It is also known for its "children picture" section. But again, it is mainly known for its beautiful gardens which are about 165,000 meters in area.