The is a river within the Hida Mountains or ''Northern Japanese Alps'', in the western region of Nagano Prefecture, Japan. The river belongs to the

Shinano River The , known as the in its upper reaches, is the longest and widest river in Japan and the third largest by basin area (behind the Tone River and Ishikari River). It is located in northeastern Honshu, rising in the Japanese Alps and flowing ...

watershed, and forms the upper section of the Sai River. The name of the river comes from the tree found in the river basin, which are used for

Azusa Yumi An is a sacred bow (''yumi'') used in certain Shinto rituals in Japan, as well as a Japanese musical bow, made from the wood of the Japanese or Japanese cherry birch tree (''Betula grossa''). Playing an ''azusa yumi'' forms part of some Shinto ...

, a sacred bow in

Shinto Shinto () is a religion from Japan. Classified as an East Asian religion by scholars of religion, its practitioners often regard it as Japan's indigenous religion and as a nature religion. Scholars sometimes call its practitioners ''Shintois ...

rituals. The river gives its name to the

Azusa (train) The ''Azusa'' ( ja, あずさ) is a limited express service operated by the East Japan Railway Company (JR East), which mainly run between and via the Chūō Main Line and Shinonoi Line. The name ''Azusa'' is taken from the Azusa River in Mat ...

limited express, which is operated by the East Japan Railway Company (JR East).

Geography

The Azusa River is 65 km long with a watershed of 559 sq km, and has its source on the southeastern slope of

Mount Yari is one of the 100 Famous Japanese Mountains. The peak lies in the southern part of the Hida Mountains (Northern Alps) of Japan, on the border of Ōmachi and Matsumoto in Nagano Prefecture and Takayama in Gifu Prefecture. The priest Banryū ...

in the

Chūbu-Sangaku National Park is a national park in the Chūbu region of Japan. It was established around the Hida Mountains and encompasses parts of Nagano, Gifu, Toyama and Niigata prefectures. It was designated a national park on December 4, 1934, along with Daisets ...

. The river flows through the valley - designated as one of Japan's National Cultural Assets, on the list of

Special Natural Monuments is a collective term used by the Japanese government's Law for the Protection of Cultural Properties to denote Cultural Properties of JapanIn this article, capitals indicate an official designation as opposed to a simple definition, e.g "Cultura ...

and

Special Places of Scenic Beauty is a collective term used by the Japanese government's Law for the Protection of Cultural Properties to denote Cultural Properties of JapanIn this article, capitals indicate an official designation as opposed to a simple definition, e.g "Cultural ...

.Kamikōchi
. The Agency for Cultural Affairs. Accessed June 28, 2008. Water from the upper reaches of Karasawa Cirque flows through Hontani and joins the Azusa River near Yokō. From here the river continues through Kamikōchi, under , and then flows through , formed in 1915 following the eruption of Mount Yake, an active volcano in the Hida Mountains. The river then flows northeast through the cities of

Azumino is a city located in Nagano Prefecture, Japan. , the city had an estimated population of 97,761 in 39744 households. and a population density of 290 persons per km2. Its total area is . Etymology of Azumino Azumino is a combination of two wo ...

and

Matsumoto Matsumoto (松本 or 松元, "base of the pine tree") may refer to: Places * Matsumoto, Nagano (松本市), a city ** Matsumoto Airport, an airport southwest of Matsumoto, Nagano * Matsumoto, Kagoshima (松元町), a former town now part of the c ...

, where it joins the Narai River near

Azumino, Nagano is a city located in Nagano Prefecture, Japan. , the city had an estimated population of 97,761 in 39744 households. and a population density of 290 persons per km2. Its total area is . Etymology of Azumino Azumino is a combination of two wo ...

, from where it becomes the Sai River, the most important tributary of the Shinano River, Japan's longest river. The river and its tributaries flow from or past several of the 100 Famous Japanese Mountains including Mount Yari, Mount Hotakadake, and Mount Yake. The Kamikōchi Line, a private railway in Matsumoto, follows the general course of the Azusa River between

Shimonii Station is a railway station in the city of Matsumoto, Nagano, Japan, operated by the private railway operating company Alpico Kōtsū. Lines Shimonii Station is a station on the Kamikōchi Line and is 4.4 kilometers from the terminus of the line at Ma ...

and

Shinshimashima Station is a railway station in Matsumoto, Nagano, Japan, operated by the private railway operating company Alpico Kōtsū. Lines Shinshimashima Station is the terminus of the Kamikōchi Line and is 14.4 kilometers from the opposing terminus of the lin ...

Water Usage

Sericulture

In his 1896 book, ''Mountaineering and Exploration in the Japanese Alps'', the English missionary and mountaineer

Walter Weston Walter Weston (25 December 1861 – 27 March 1940), was an English clergyman and Anglican missionary who helped popularise recreational mountaineering in Japan at the turn of the 20th century. Background and early life Weston was born 25 De ...

wrote that the Azusa River was used to power machinery used in

sericulture Sericulture, or silk farming, is the cultivation of silkworms to produce silk. Although there are several commercial species of silkworms, '' Bombyx mori'' (the caterpillar of the domestic silkmoth) is the most widely used and intensively stud ...

, "The simple machinery for winding off the silk from the cocoons is water powered and gives employment to a score of bright-faced girls, varying from twelve to twenty years of age."

Hydroelectricity

Several dams are operated by Tokyo Electric Power Company, or TEPCO, along the river, including: the

Nagawado Dam Nagawado Dam ( ja, 奈川渡ダム) is a dam in Nagano Prefecture, Japan, on the Azusa River completed in 1969.Midono Dam Midono Dam ( ja, 水殿ダム) is a dam on the Azusa River in the Nagano Prefecture, Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and i ...

; and the

Inekoki Dam is a dam along the Azusa River in Matsumoto, Nagano Prefecture, Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the we ...

. The dams use pumped-storage hydroelectricity, and are collectively referred to as the ''Azusagawa 3 dams''.

Irrigation

Several weirs, canals, and underground channels draw water from the Azusa River that are used for irrigation, including for wasabi farming in Azumino. The Wada Weir is thought to have been completed in 973.あずさ書店編集部『幻の大寺院若沢寺を読みとく』あずさ書店、2010年9月、ISBN 9784900354678、43ページ

References