What Is the Inari River Third Sabo Dam?
The Inari River Third Sabo Dam (稲荷川第三砂防堰堤, Inarigawa Daisan Sabō Entei) is a concrete gravity erosion-control dam built in 1921 on the Inari River in the Nakasuzu area of Nikko City, Tochigi Prefecture, and registered in 2002 as a Registered Tangible Cultural Property (Structure) of Japan, with effect from 21 August. It measures 76 meters long and 5.8 meters high and is owned by the national government (Ministry of Land, Infrastructure, Transport and Tourism).
The dam stands 84 meters upstream of the Second Dam, and the next registered dam upstream, the Tenth, is about 600 meters farther on. It is the uppermost of the four closely spaced lower dams and the longest of all seven registered Inari River Sabo Dams. The Nikko Sabo Office dates its completion to 1 July 1921.
A Crest 3.3 Meters Wide
The feature the Agency for Cultural Affairs singles out at the Inari River Third Sabo Dam is the width of its crest, the flat top of the dam. At 3.3 meters it is broader than on the dams built later in the program.
Debris flows on the Inari carry big boulders along with the water. Stones going over a dam strike the edge of the crest, and the upper part of the structure takes the blow. The agency reads the broad crest as a direct expression of the early dams' shape, designed when engineers expected severe impacts from large rolling rocks. In the first years of the program, in other words, the answer to boulders was mass: make the top of the dam thick enough to take the hits.
In plan the dam runs straight across the valley. Like the others, its face is laid in Tanizumi, stones set on the diagonal, with the joints mortared as Nerizumi. The Japan Society of Civil Engineers records a repair in 2006.
Why the Inari River Third Sabo Dam Was Registered
The Inari River Third Sabo Dam has registration number 09-0057 and was registered for contributing to the historic landscape of the nation. Together with the Second and Fourth Dams just below it, it steps down a narrow mountain valley framed by rock and forest. In its description of the Fourth Dam, the Agency for Cultural Affairs calls the upstream view running on to the Second and Third Dams a historic modern river landscape.
What to Look for at the Inari River Third Sabo Dam
The Inari River Third Sabo Dam is an outdoor facility with no admission fee, seen from the path along the river. Climbing onto the dam or walking along its crest is not permitted.
The thickness of the crest is easier to judge from an angle than head-on. In drier spells, when only a thin sheet of water spills over the notch, you can make out the line of stones along the crest edge and how deep the top of the dam runs back. The 76-meter wall crossing the valley in a straight line also makes an instructive contrast with the 40-meter Second Dam just downstream. Directions to the dams are on the Inari River Sabo Dams page.
- 📍 Plan Your Visit to Tochigi
- Find tours, activities & transport passes near Inari River Third Sabo Dam
- [ Nikko Toshogu Shrine & Kegon Falls Day Trip ]
Q&A
- When was the Inari River Third Sabo Dam built?
- In 1921. The Nikko Sabo Office gives a completion date of 1 July 1921.
- How big is the Inari River Third Sabo Dam?
- It is 76 meters long and 5.8 meters high, the longest of the seven registered Inari River Sabo Dams. The Japan Society of Civil Engineers gives the length as 75.5 meters.
- Why is the crest of the Inari River Third Sabo Dam so wide?
- It is understood as protection against large boulders carried by debris flows. The crest is 3.3 meters wide, broader than on later dams, and the Agency for Cultural Affairs cites it as typical of the early dams.
- Where exactly is the Inari River Third Sabo Dam?
- On the Inari River in the Nakasuzu area of Nikko, 84 meters upstream of the Second Dam. The Tenth Dam is about 600 meters farther upstream.
- Can I visit the Inari River Third Sabo Dam, and is there a fee?
- Yes, you can view it from the riverside path free of charge. As a working erosion-control dam it is closed to climbing, including the crest.
Basic Information
| Name | Inari River Third Sabo Dam (稲荷川第三砂防堰堤) |
|---|---|
| Location | Aza Nakasuzu, Oaza Nikko, Nikko City, Tochigi Prefecture |
| Designation | Registered Tangible Cultural Property (Structure) |
| Year Designated | Registered in 2002 |
| Quantity | 1 structure |
| Dimensions | 76 meters long, 5.8 meters high, crest 3.3 meters wide (concrete gravity dam) |
| Owner | Government of Japan (Ministry of Land, Infrastructure, Transport and Tourism) |
| Public Access | Outdoor erosion-control facility; exterior viewable from the riverside path (no fee) |
References
- Agency for Cultural Affairs, Database of National Cultural Properties: Inari River Third Sabo Dam
- https://kunishitei.bunka.go.jp/bsys/maindetails/101/00002883
- Agency for Cultural Affairs, Database of National Cultural Properties: Inari River Fourth Sabo Dam
- https://kunishitei.bunka.go.jp/bsys/maindetails/101/00002881
- Cultural Heritage Online: Inari River Third Sabo Dam
- https://online.bunka.go.jp/heritages/detail/182793
- MLIT Kanto Regional Development Bureau, Nikko Sabo Office: History of the Registered Sabo Dams (Japanese)
- https://www.ktr.mlit.go.jp/nikko/nikko00038.html
- Japan Society of Civil Engineers, Kanto Branch: Sabo Dams of the Inari River Basin, Nikko (Japanese)
- https://www.jsce.or.jp/branch/kanto/04_isan/h26/h26_3.html
- Tochigi Prefecture Cultural Properties: Inari River Third Sabo Dam (Japanese)
- https://bunkazai.pref.tochigi.lg.jp/cultural/%E3%80%90%E7%A8%B2%E8%8D%B7%E5%B7%9D%E7%AC%AC%E4%B8%89%E7%A0%82%E9%98%B2%E5%A0%B0%E5%A0%A4%E3%80%91/
Last verified: 2026.10.01
