Okutama Lake is located on the border of Tokyo and Yamanashi. It is a man made lake formed by Ogochi Dam that blocks Tamagawa River. It is called as a water reservoir as it serves the important role of supplying most of Tokyo’s drinking water. When the weather is nice, the reflection of the mountains on the lake is so stunning that many tourists visit this lake by bus from Okutama Station or by car. Fishing there seems to be another popular activity.