白川郷 (Shirakawa-go) is a UNESCO world heritage site situated in 岐阜県 (Gifu prefecture). It is famous for the way house are constructed: 合掌造り (gasho-zukuri).
From 東京 (Tokyo), 白川郷 (Shirakawa-go) can be accessed by a succession of train and bus. The trip is quite long and it is therefore preferable to stay several days.
Travel tips: The village is inaccessible in winter due to snow. The place is romantic, go with somebody you like very much :)
Please check the photos of my visit in August 2006.