Old Kitakami River

...The longitudinal valley basin from the foot of Mt. Nishidake near the source to the Kozenji Gorge in the south is called the Kitakami Basin. At Yanaizu in Tsuyama Town, Motoyoshi County, the river splits into the old and new Kitakami Rivers, and the water from upstream flows south through the gorge of the New Kitakami River on the west side, and flows east from Iinogawa in Kahoku Town to become the Oiha River and empty into Oiha Bay. The old Kitakami River on the east side dams the main stream water at Yanaizu Watergate, and merges with its tributaries, the Hasama River and the Eai River, before flowing into Ishinomaki Bay.

*Some of the terminology that refers to the "Old Kitakami River" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…源流部付近の西岳山麓から南の狐禅寺峡谷までの縦谷盆地を北上盆地という。本吉（もとよし）郡津山町の柳津（やないづ）で新旧北上川に分かれ，上流からの水は西側の新北上川の峡谷を南流し，河北町飯野川から東流して追波川となり追波湾に注ぐ。東側の旧北上川は，柳津水門で本流の水をせき止め，支流の迫（はさま）川，江合（えあい）川を合流して石巻湾に注ぐ。…

※「旧北上川」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報