Constructed back in 1993, the Sagurigawa Dam was built for the purposes of flood control and generating hydro power. This part of Niigata Prefecture receives some of the heaviest snowfalls not just in Japan but on Earth, and when that snow melts the abundant water needs to be managed. The dam has also become something of a tourist destination in itself, owing to the fantastic views you can get from the site.
Part of the appeal of Sagurigawa Dam comes from the vast differences in the views you'll get here depending on the season. I've visited in two seasons - summer and autumn - and the lush greens that I had witnessed during the warmer months made way for the beautiful reds, oranges and yellows of fall. Because of the extreme amount of snowfall that the area receives, the roads to the dam are closed throughout winter, but spring at the dam means many beautiful blooms to enjoy - particularly the cherry blossoms and rhododendrons. The date that the roads reopen after winter varies, but is generally announced on the Sagurigawa Dam website (in Japanese). Be sure to check if you plan on visiting in early spring, just to ensure you can safely access the area.
If you appreciate great views, a spectacular natural environment, or simply marveling at the wonders of man-made engineering, a visit to Sagurigawa Dam is worth your while.
