Final answer:
The Yukon River is the largest river in Alaska and Yukon, flowing northward in the Yukon Territory of northern Canada, and empties into the Bering Sea.
Step-by-step explanation:
The river described in the question is the Yukon River. It flows northward in the Yukon Territory of northern Canada, and empties into the Bering Sea. The Yukon River is the largest river in Alaska and Yukon, and passes through Whitehorse and Dawson City. It also has the Teslin, Porcupine, and Tanana Rivers as its tributaries.