Jamma River
Abay
['Essequibo River', 'Brisbane River', 'Piscataqua River', 'Orinoco', 'Kansas River', 'Yamuna River', 'Newark Bay', 'Sobat River', 'Lake Victoria', 'Arkansas River', 'Lake Beloye', 'River Elbe', 'Vistula River', 'Tonawanda Creek', 'River Doe', 'Wei River', 'Apalachicola River', 'Hoosic River', 'James River', 'Parramatta River', 'Indus', 'Chusovaya River', 'river Ourthe', 'Angara River', 'Pine Creek', 'Suwannee River', 'Indian Ocean', 'Cauvery', 'Orontes River', 'Liard', 'Jefferson River', 'Narew River', 'Long Island Sound', 'Iset River', 'Fraser River', 'Penobscot River', 'Ob basin', 'Uruguay River', 'Hawkesbury River', 'river Weser', 'Don River', 'Vardar', 'Irrawaddy', 'Murrumbidgee River', 'Rybinsk Reservoir', 'Mediterranean', 'Adour', 'Ohio', 'Peace River', 'Oder', 'Atlantic Ocean', 'Sacramento', 'Delaware River', 'Kanawha River', 'Katun River', 'Dniester', 'Big Horn River', 'Oglio', 'Tioughnioga River', 'Ussuri River', 'Amazon River', 'Kura River', 'Ufa River', 'Yarra River', 'Passaic River', 'Quesnel River', 'Altamaha River', 'Bering Sea', 'Champlain', 'Allegheny River', 'Godavari', 'Krishna', 'Yukon River', 'Red Deer River', 'Torne River', 'Hai River', 'Euphrates', 'Ruhr River', 'Tasman Sea', 'River Foyle', 'Christina River', 'Somme', 'Kolubara', 'Kama River', 'Illinois', 'Xingu River', 'Stikine River', 'Pranhita', 'Tobol River', 'Columbia River', 'Red River', 'Bodrog river', 'Bristol Bay', 'Koksoak River', 'Upper Amazon', 'Gauley River', 'Santa Maria River', 'Laptev', 'Segre']
Jamma River
The Jamma River is a river in central Ethiopia and a tributary of the Abay (or Blue Nile) on its right side. It drains parts of the Semien Shewa Zones of the Amhara and Oromia Regions. The Upper Jamma flows through steep, deep canyons cut first through volcanic rock and then through the Cretaceous sandstone and shaly sandstone, with Jurassic limestone at the bottom. It has a drainage area of about 15,782 square kilometers in size. Tributaries include the Wanchet. The earliest mention of this river is in the Gadla of Tekle Haymanot, which was written in the fourteenth century. One of the earliest European mentions is by the missionary Pedro Páez, who was the first European to see and describe the origin of the Abay. According to Johann Ludwig Krapf, in the 1840s the Jamma defined the boundary between Marra Biete and Moret, two districts of the former province or Sultanate of Shewa.