Azukisawa Sabo Dams

Stone Check Dams from the Taishō Era

The Azukisawa Sabo Dams (小豆沢砂防堰堤群) are a series of stone erosion control dams built in 1919 and 1920 in a side valley at Azukisawa, Miyagawa-cho, Hida City, Gifu Prefecture, and three of them, Nos. 1 to 3, were entered on the national register as Registered Tangible Cultural Properties on March 29, 2019. All three are dry-stone structures laid entirely by hand, and all belong to Gifu Prefecture.

Azukisawa is pronounced "ah-zoo-kee-sah-wah" and literally means "red bean stream." The hamlet sits in a narrow stretch of the Miyagawa valley near the northern tip of Hida City, a few kilometers short of the Toyama border, where National Route 360 and the JR Takayama Line squeeze in beside the river. The dams stand on a short tributary that drops out of the hills west of the houses. Sabo, the Japanese word used in the dams' official names, refers to the work of holding back sediment on mountain streams before it can bury the settlements below.

The 1914 Disaster Behind the Azukisawa Sabo Dams

The Azukisawa Sabo Dams trace back to a single day of rain. According to the Jinzu River Sabo Office of the Ministry of Land, Infrastructure, Transport and Tourism, on August 13, 1914, eight ravines in what was then Sakashita Village, including two named Azukisawa Ōtani and Azukisawa Takidani, poured so much debris into the Miyagawa that the river was dammed and the valley floor turned into a lake. Within today's Miyagawa-cho, 36 people died, 49 houses were swept away and 74.3 hectares of farmland were lost.

In response, the national government ran a directly managed sabo program on the Miyagawa from July 1919 to September 1930. The prefecture's signboard at the site says five dams were built on the Azukisawa tributary under that program; three of them are the registered group. The Agency for Cultural Affairs describes the lowest of them, No. 1, as the first sabo facility ever installed anywhere in the Jinzu River system.

On the same day in 2019, five dams in the Kuwatani valley, also in Miyagawa-cho, and two in the Rokurodani valley in Kamioka were registered as well. The Furukawa Civil Engineering Office of Gifu Prefecture presents them together as the surviving works of the program that followed the 1914 floods.

How the Three Dams Are Laid Out

The three Azukisawa Sabo Dams are numbered from the bottom of the valley upward. The national database gives these dates and dimensions:

• No. 1 Sabo Dam: completed 1919; crest length 36 m, height 5.5 m; the lowest of the three
• No. 2 Sabo Dam: completed 1920; crest length 30 m, height 4.5 m; about 200 m above No. 1
• No. 3 Sabo Dam: completed 1920; crest length 25 m, height 5.5 m; about 240 m above No. 2

That puts three steps of masonry within roughly 440 meters of stream. The registration numbers run consecutively from 21-270 to 21-272, and each was registered under the same criterion, as a structure that contributes to the historic landscape of the country.

No. 1 sits just behind the hamlet, close to garden walls and houses. Above it the valley tightens, and Nos. 2 and 3 lie deep in a wooded ravine. The photographs on the prefecture's signboard show how differently each has aged: water slides down the face of No. 2 in a thin sheet, while No. 3 has had its lower half buried by trapped gravel until it reads almost as part of the slope. Walked in order, the three show a century of a mountain stream being slowly brought to rest. Each dam's construction is covered on its own page.

Visiting the Azukisawa Sabo Dams

The Azukisawa Sabo Dams are working flood-control structures, not a staffed site, so there are no opening hours and no admission fee. Beside the road in the hamlet, Gifu Prefecture has put up an information board and a memorial stone; the board carries a map marking all three dams, a photo of each and a short history in Japanese. It is the best place to get your bearings.

We could find no published walking route to the upper two dams in the prefecture's materials (checked September 25, 2026). The ravine is steep, and you should not climb onto the dams or wade into the stream. Stay away from the valley during and after heavy rain, when the water rises quickly.

The nearest station is Sugihara on the JR Takayama Line, an unstaffed stop that is the northernmost station in Gifu Prefecture. From there it is about 2 km north along National Route 360 to Azukisawa, a walk of 25 to 30 minutes by our map estimate. Trains are infrequent, so check the timetable before you set out. Service between Sugihara and Inotani was suspended from March 18, 2026 because of scour around a bridge pier and resumed on May 30, 2026. By car, follow Route 360 north from central Furukawa in Hida City. No dedicated parking is signposted.