Tumen River

River in China, North Korea, and Russia

The Tumen River, also known as the Tuman River or Duman River, is a 521-kilometre (324 mi) long river that serves as part of the boundary between China, North Korea (right) and Russia (left), rising on the slopes of Mount Paektu and flowing into the Sea of Japan. The river has a drainage basin of 33,800 km2 (13,100 sq mi).

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