Despite being considered a remote location, it's not that far from Omachi Station by car. You can park your car in the large parking lot in front of Nanokura Sanso (mountain lodge) and take a taxi from the taxi stand in front of Nanokura Sanso to the dam. If you specify your return time, a taxi will be waiting for you. After walking through the long tunnel from the dam's entrance, you can enjoy spectacular views of the Takase Valley and the Northern Alps.
However, the tunnel is long and dark, and there is traffic from dam personnel's vehicles, so it is recommended to bring a flashlight.
This was part of a rental bicycle route, a route I took from the station, enjoying the ups and downs along the way.
It was the season of fresh greenery, so the air was slightly cool, the sky was bright, and the lake and river flowed with beautiful jade and emerald-green leaves. There was plenty of shade from the trees, making me imagine how spectacular the autumn foliage must be. It was a wonderful place.