These are the Rivers of Japan.

Hokkaidō
There are 316 rivers in Hokkaidō.

List of rivers in Hokkaidō by length
The following table is a list of rivers of Hokkaidō by length.

List of class 1 rivers in Hokkaidō
The following is a list of the 15 first class rivers (1級河川) under management by the :
 Abashiri River
 Ishikari River
 Koetoi River
 Kushiro River
 Mu River
 Rumoi River
 Saru River
 Shibetsu River
 Shiribeshi-Toshibetsu River
 Shiribetsu River
 Shokotsu River
 Teshio River
 Tokachi River
 Tokoro River
 Yūbetsu River

Honshu

Tōhoku Region 
First class rivers under the control of Tohoku Regional Bureau (東北地方整備局)
Iwaki River (岩木川) - Aomori
 Takase River 高瀬川 - Aomori
Mabechi River (馬淵川) - Iwate, Aomori
Kitakami River (北上川) - Iwate, Miyagi
Naruse River (鳴瀬川) - Miyagi
 Natori River (名取川) - Miyagi
Abukuma River (阿武隈川) - Miyagi, Fukushima
Yoneshiro River (米代川) - Akita, Iwate
Omono River (雄物川) - Akita
 Koyoshi River (子吉川) - Akita
 Mogami River (最上川) - Yamagata
 Aka River (赤川) - Yamagata

Second class river
Oirase River (奥入瀬川)

Hokuriku region 
First-class rivers under the control of Hokuriku Regional Bureau (北陸地方整備局)
 Ara River (荒川) - Yamagata, Niigata
 Agano River (阿賀野川) - Hukushima, Gunma, Niigata
 Shinano River (信濃川) - Nagano, Gunma, Niigata
 Seki River (関川) - Nagano, Niigata
 Hime River (姫川) - Nagano, Niigata
 Kurobe River (黒部川) - Toyama
 Jōganji River (常願寺川) - Toyama
 Jinzū River (神通川) - Gifu, Toyama
 Shō River (庄川) - Gifu, Toyama
 Oyabe River (小矢部川) - Ishikawa, Toyama
 Tedori River (手取川) - Ishikawa
 Kakehashi River (梯川) - Ishikawa

Chūbu region 

Rivers that flow into the Sea of Japan:

Agano-gawa (阿賀野川) - Niigata, Fukushima, Gunma
Shinano-gawa (信濃川) or Chikuma-gawa (千曲川) - longest of Japan
Seki-kawa (関川) - Nagano, Niigata
Hime-kawa (姫川) - Nagano, Niigata
Kurobe-gawa (黒部川) - Toyama
Jōganji-gawa (常願寺川) - Toyama
Jinzū-gawa (神通川) - Gifu, Toyama
Shō-gawa (庄川) - Gifu, Toyama
Oyabe-gawa (小矢部川) - Toyama, Ishikawa
Tedori-gawa (手取川) - Ishikawa
Kuzuryū-gawa (九頭竜川) - Gifu, Fukui

Rivers that flow into the Pacific Ocean:

Fuji-kawa (富士川) - Nagano, Yamanashi, Shizuoka
Abe-kawa (安倍川) - Shizuoka
Ōi-gawa (大井川) - Shizuoka
Tenryū-gawa (天竜川) - Nagano, Aichi, Shizuoka
Toyo-gawa (豊川) - Aichi
Yahagi-gawa (矢作川) - Nagano, Gifu, Aichi
Shōnai-gawa (庄内川) - Gifu, Aichi
Kiso-gawa (木曽川) - Nagano, Gifu, Aichi, Mie
Nagara-gawa (長良川) - Gifu, Aichi, Mie
Ibi-gawa (揖斐川) -Gifu, Mie
Kushida-gawa (櫛田川) - Mie
Miya-gawa (宮川) - Mie

First class rivers under control of Chubu Regional Bureau (中部地方整備局)
 Kano-gawa 狩野川 - Shizuoka
 Abe-kawa 安倍川 - Shizuoka
Ōi-gawa 大井川 - Shizuoka
 Kiku-gawa 菊川 - Shizuoka
Tenryū-gawa 天竜川 - Nagano, Aichi, Shizuoka
Toyo-gawa 豊川 - Aichi
Yahagi-gawa 矢作川 - Nagano, Gifu, Aichi
Shōnai-gawa 庄内川 - Gifu, Aichi
Kiso-gawa 木曽川 - Nagano, Gifu, Shiga, Aichi, Mie
 Suzuka-gawa 鈴鹿川 - Mie
 Kumozu-gawa 雲出川 - Mie
 Kushida-gawa 櫛田川 - Mie
 Miya-gawa 宮川 - Mie

Kansai 
The first class rivers under the control of Kinki Regional Bureau (近畿地方整備局)
 Kuzuryu-gawa 九頭竜川
 Kita-gawa 北川 - Shiga, Fukui
 Yura-gawa :ja:由良川 - Hyogo, Kyoto
Yodo-gawa (淀川), Seta-gawa (瀬田川) or Uji-gawa (宇治川)
Yasu-gawa (野洲川)
Katsura-gawa (桂川), Hozu-gawa (保津川) or Ōi-gawa (大堰川)
Kamo-gawa (鴨川)
Kizu-gawa (木津川)
Dōton-bori (道頓堀)
Yamato-gawa (大和川) - Nara, Osaka
 Maruyama-gawa (円山川) - Hyogo
 Kako-gawa (加古川) - Hyogo
 Ibo-gawa (揖保川) - Hyogo
 Ki-no-kawa (紀ノ川, 紀の川) - Nara, Wakayama
 Yamato-gawa (大和川) - Nara, Osaka
 Kumano-gawa (熊野川) or Shingu-gawa (新宮川)- Nara, Mie, Wakayama

The second class river	
Muko-gawa (武庫川)

Chūgoku 
First class rivers under control of Chugoku Regional Bureau (中国地方整備局)
Sendai River (千代川) - Tottori
Tenjin River (天神川) - Tottori
Hino River (日野川) - Tottori
Hii River (斐伊川) - Shimane, Tottori
Gō-no-kawa, or Gō-gawa (江の川, 江川) - Hiroshima, Shimane
Takatsu River (高津川) - Shimane
Yoshii River 吉井川 - Okayama
Asahi River 旭川 - Okayama
Takahashi River (高梁川) - Hiroshima, Okayama
Ashida River 芦田川 - Okayama, Hiroshima
Ōta-gawa (太田川) - Hiroshima
Ose River 小瀬川 - Hiroshima, Yamaguchi
Saba River 佐波川 - Yamaguchi

Shikoku 
First class rivers under control of Shikoku Regional Bureau (四国地方整備局)
Yoshino-gawa (吉野川) - Kochi, Ehime, Tokushima, Kagawa
 Naka-gawa 那賀川 - Tokushima
 Doki-gawa 土器川 - Kagawa
 Shigenobu-gawa 重信川 - Ehime
 Hiji-kawa :ja:肱川 - Ehime
 Monobe-kawa 物部川 - Kochi 	6
 Niyodo-gawa 仁淀川 - Ehime, Kochi
Shimanto-gawa (四万十川) - Ehime, Kochi

Kyūshū 
First class rivers under control of Kyushu Regional Bureau (九州地方整備局)

 Onga-gawa 遠賀川 - Fukuoka
 Yamakuni-gawa 山国川 - Oita, Fukuoka
Chikugo-gawa (筑後川) - Kumamoto, Oita, Fukuoka, Saga
 Yabe-gawa 矢部川 - Fukuoka
 Matsuura-gawa 松浦川 - Saga
 Rokkaku-gawa 六角川 - Saga
 Kase-gawa 嘉瀬川 - Saga
 Honmyo-gawa 本明川 - Nagasaki
 Kikuchi-gawa 菊池川 - Kumamoto
 Shira-kawa 白川 - Kumamoto
 Midori-gawa 緑川 - Kumamoto
Kuma-gawa (球磨川) - Kumamoto
 Ōita-gawa 大分川 - Ōita
 Oono-gawa 大野川 - Kumamoto, Miyazaki, Ōita
 Banjo-gawa 番匠川 - Ōita
 Gokase-gawa 五ヶ瀬川 - Kumamoto, Ōita, Miyazaki
 Omaru-gawa 小丸川 - Miyazaki
 Ōyodo-gawa 大淀川 - Kagoshima, Kumamoto, Miyazaki
 Sendai-gawa 川内川 - Miyazaki, Kagoshima
 Kimotsuki-gawa 肝属川, 肝付川 - Kagoshima

References

 全国１０９の一級水系 (109 of first class rivers; by Ministry of Land, Infrastructure and Transport, Japan)
 一級水系の河川整備基本方針策定状況（平成21年3月6日現在） (you can see where first class rivers are)

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