When I visited a construction site of a dam about 20 years ago, I was shocked by the gigantic concrete structure. It appeared suddenly in a remote mountain area. The dam is 100 meters in height and 400 meters wide, which bears the pressure of more than 100 million of water. There are no useless functions. It is built only for the purpose. Therefore, the functional beauty of the dam stands out. I was attracted to it. Dams are built for water control and power production by clearing nature in the first place. They are necessary not only for people’s comfortable living but have a role in protecting us from natural disasters such as floods. At the beginning of the construction, it looks just a human-made structure that opposes nature. However, as time passes, I think the dam will become a part of nature.