The Takahashi River is a Class A river that flows through western Okayama Prefecture.
Together with the Yoshii and Asahi rivers, it is counted as one of Okayama’s three major rivers. Including its basin in Okayama and Hiroshima prefectures, it has the largest basin area of the three.
Its main tributaries include the Nariwa River and the Oda River. The basin is primarily in the former Bichu Province, with parts of its tributary basins extending into Hiroshima Prefecture.
The river rises at Mt. Hanamiyama (elevation: 1,188 meters; Niimi City), cuts through the Kibi Plateau, and empties into Mizushima-nada in the Seto Inland Sea (Kurashiki City). From ancient Kibi Province to medieval Niimi-no-Sho, early-modern Bitchu Matsuyama, modern Kurashiki, and today’s Mizushima Industrial Complex, the basin is home to the history, culture, and industries of each era.
At the proposal of Ohara Soichiro, who succeeded Ohara Magosaburo (the businessman who founded the Ohara Museum of Art), the Takahashi River was regarded as a “shared destiny,” and the Takahashi River Basin Alliance was established in 1954.
In keeping with this purpose, in 2015, seven cities and three towns in the basin signed a cooperation agreement to form the Takahashi River Basin Intermunicipal Partnership, and are working together to develop the region as a whole.
- Kurashiki City
- Niimi City
- Takahashi City
- Soja City
- Hayashima Town
- Yakage Town
- Ibara City
- Asakuchi City
- Satosho Town
- Kasaoka City
Kurashiki City

Located at the mouth of the main stream of the Takahashi River, the city has distinct cultures and industries rooted in each of its areas, including the former Kurashiki area, home to the Bikan Historical Area, as well as Kojima, Tamashima, Chayamachi, and Mabi and Funao.
The Mizushima area, facing the Seto Inland Sea, is home to an industrial complex with the largest value of industrial shipments in western Japan.
Mabi, which was damaged in the July 2018 heavy rains, is also known as the home of Kibi no Makibi, a politician and scholar of the Nara period. It hosted the G7 Education Ministers’ Meeting in 2016.
| Area | 356.07 square kilometers |
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| Total population | 459,510 (as of September 1, 2026) |
Niimi City

Located in the northwestern part of Okayama Prefecture, Niimi has a limestone karst plateau in the southeastern part of the city. In winter, the mountain areas receive abundant high-quality snow. Situated upstream on the Takahashi River, it is home to ayu and amago trout. Limestone caves, including Ikurado Cave, are found in the south.
From the Heian period through the Warring States period, the area prospered as an imperial estate and an estate of Toji Temple in Kyoto, and has preserved traditional culture such as Watari Byoshi and taiko rice-planting performances.
Today, local specialties include agricultural products such as Chiyagyu Beef.
| Area | 793.29 square kilometers |
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| Total population | 24,313 (as of September 1, 2026) |
Takahashi City

The main stream of the Takahashi River and one of its major tributaries, the Nariwa River, flow through the city.
From autumn to winter, a sea of clouds can often be seen from scenic vantage points. Bitchu Matsuyama Castle, one of Japan’s few surviving mountain castles, is known as the “Castle in the Sky.”
The Fukiya area once prospered as a bengara production center, and its streetscape of red plaster walls remains today.
The area has valued education since the Edo period. In the Meiji period, it was the first in Okayama Prefecture to establish schools such as Junsei Girls’ School.
| Area | 546.99 square kilometers |
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| Total population | 25,003 (as of September 1, 2026) |
Soja City

The area is said to have once been the center of ancient Kibi Province, and numerous large and small burial mounds, as well as Bichu Kokubun-ji Temple, remain here.
The city is home to a legend about Prince Kibitsuhiko, sometimes said to have inspired the Momotaro legend, and the demon Ura. It also has the ruins of Kinojo Castle, said to have been built by the ancient Yamato court. The city is also known as the birthplace of the great painter Sesshu.
| Area | 212.01 square kilometers |
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| Total population | 68,507 (as of September 1, 2026) |
Hayashima Town

It is the smallest town in Okayama Prefecture by area and has the highest population density.
Surrounded on all sides by Okayama City and Kurashiki City, it serves as a bedroom community for both.
An important transportation hub, the Okayama Prefectural Distribution Center, one of the largest of its kind in the Chugoku and Shikoku regions, straddles Hayashima Town and Okayama City. The convention facility Convex Okayama is also located there.
| Area | 7.62 square kilometers |
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| Total population | 12,557 (as of September 1, 2026) |
Yakage Town

A post town on the old Sanyo Road, Yakage has a record of Atsuhime staying there while traveling from Satsuma to Edo to marry into the shogun’s family.
The town center still retains its historic streetscape, including the former honjin and waki-honjin inns. Today, efforts are also underway to renovate old houses into accommodation and other facilities.
The Oda River, one of the major tributaries of the Takahashi River, flows through the town. Its main industry is agriculture, while commerce and tourism have also been growing in recent years.
| Area | 90.62 square kilometers |
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| Total population | 12,141 (as of September 1, 2026) |
Ibara City

Apart from the city center, which spreads across the basin of the Oda River, a tributary of the Takahashi River, most of the area is made up of farming and mountain villages surrounded by mountains.
The former Bisei Town called itself the “Town of Astronomy” and enacted Japan’s first Light Pollution Prevention Ordinance in 1989. The Bisei Spaceguard Center is also the world’s first facility designed to observe space debris and other objects.
The area is considered the birthplace of the song “Chinese Lullaby,” arranged by Kosaku Yamada.
| Area | 243.54 square kilometers |
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| Total population | 34,644 (as of September 1, 2026) |
Asakuchi City

Located in the southwestern part of Okayama Prefecture, the city is traversed by the Satomi River, a tributary of the Oda River.
The city is home to many traditional and local industries with long histories, including noodle-making, sake brewing, horticulture, cap-making, and straw production.
Because the area is well suited to astronomical observation, Kyoto University Okayama Observatory was established here. One of Asia’s largest telescopes, named the Seimei Telescope after the local legend of Abe no Seimei, is in operation.
Asakuchi City’s Konko Town has a history of prospering as a temple town around the headquarters of Konkokyo, and retains a streetscape with a retro atmosphere.
| Area | 66.46 square kilometers |
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| Total population | 29,985 (as of September 1, 2026) |
Satosho Town

Located in the southwestern part of Okayama Prefecture, the town is traversed by the Satomi River, a tributary of the Oda River, and the Shinjo River.
Its main industry is agriculture, and food-processing factories are also scattered throughout the town.
The town is working to build a brand for makomotake (Manchurian wild rice shoots), considered a luxury ingredient in Chinese cuisine, which can also be enjoyed at local restaurants.
The birthplace of Yoshio Nishina, considered the father of nuclear physics in Japan.
| Area | 12.23 square kilometers |
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| Total population | 10,332 (as of September 1, 2026) |
Kasaoka City

Located in southwestern Okayama Prefecture, Kasaoka also has cultural and economic ties with the Bingo region, whose central city is Fukuyama City in Hiroshima Prefecture.
Facing the Seto Inland Sea, the city is home to the vast Kasaoka Bay reclamation area to the south and the Kasaoka Islands, made up of 31 islands of various sizes. Oehama is a breeding ground for horseshoe crabs, “living fossils,” and has been designated a national natural monument.
Shiraishi Odori, passed down on Shiraishi-jima Island in the Kasaoka Islands, has been designated an Important Intangible Folk Cultural Property of Japan.
| Area | 136.07 square kilometers |
|---|---|
| Total population | 40,574 (as of September 1, 2026) |
