river, east-central Alaska, U.S. Its name is an Athabascan word meaning “river trail.” An important tributary of the Yukon River, it rises from two headstreams, the Chisana and Nabesna rivers on the north side of the Alaska Range, and it flows some 570 miles (915 km) from the head of the Chisana northwestward along the base of the Alaska Range to join the Yukon River near the village of Tanana. The river drains the north slopes of the high Alaska Range and is fed by a number of glaciers. The river drains approximately 44,000 square miles (114,000 square km) of interior Alaska. The Tanana and White rivers together contribute almost 30 percent of the total water flow of the Yukon River, though they make up only about 20 percent of its drainage area. The sediment-laden Tanana is rich in minerals. Its flow peaks in July, and by late summer it becomes a shallow stream. The river was first explored by Russian traders in the mid-19th century. The Tanana valley, an important gold-producing area made famous in 1904 by the gold rush, is also a lumbering district and one of Alaska's major farming regions, producing potatoes, truck crops, and small grains. Fairbanks, the terminus of the Alaska and Richardson highways (which follow the river west of Yukon Territory, Canada) and of the Alaska Railroad (from the port of Seward), is the commercial and distribution centre of the Tanana valley. In 1967 the river overflowed, flooding Fairbanks. Along the river is Tetlin National Wildlife Refuge and Tanana Valley State Forest.