The Yukon River is a major watercourse of northwestern North America. From its source in British Columbia, Canada, it flows through Canada's territory of Yukon. The lower half of the river continues westwards through the U.S. state of Alaska. The river is 3,190 kilometres long and empties into the Bering Sea at the Yukon–Kuskokwim Delta. The average flow is 6,400–7,000 m³/s. The total drainage area is 833,000 km², of which 323,800 km² lies in Canada. The total area is more than 25% larger than Texas or Alberta.
The longest river in Alaska and Yukon, it was one of the principal means of transportation during the 1896–1903 Klondike Gold Rush. A portion of the river in Yukon—"The Thirty Mile" section, from Lake Laberge to the Teslin River—is a national heritage river and a unit of Klondike Gold Rush International Historical Park. Paddle-wheel riverboats continued to ply the river until the 1950s, when the Klondike Highway was completed. After the purchase of Alaska by the United States in 1867, the Alaska Commercial Company acquired the assets of the Russian-American Company and constructed several posts at various locations on the Yukon River.