The Toyonenike Dam (weir) boasts a 145-meter-long, 30-meter-high stone-masonry multiple arch structure, featuring five arches and six buttresses in the center, making it a rare civil engineering heritage site. Designated a National Important Cultural Property in 2006, the texture of the stone surfaces testifies to the years of wind and rain.

The surrounding area is shrouded in silence, and its silhouette at dusk resembles a medieval castle. There are no nighttime lights, so visiting before sunset is recommended, but visiting during quieter hours offers a truly extraordinary atmosphere.

Promenades along the lakeside allow for close-up views from the riverbed below the dam and from viewpoints at the top of the arches. Cherry blossoms in spring and autumn foliage illuminate the dam, making it a popular destination for photographers and motorists. Every summer, a water release ceremony called "Yuru-nuki" is held, offering a glimpse of the local agricultural culture along with the splashes of water.
Toyonenike Yuru-nuki takes place when the water level of downstream Iseki Pond is reduced to about 30%. Announcements will be made in advance on the dam's website, etc.

The area around the dam is surrounded by rich nature, making it a great place to enjoy outdoor activities such as hiking and camping.