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.