Dalles, the

City and administrative headquarters of Wasco County, north-central Oregon, on the Columbia River, 113 km/70 mi east of Portland; population (1990) 11,100. Industries include aluminium production, timber and flour milling, salmon canning, and fruit processing.

The Dalles Dam, 5 km/3 mi to the northeast, completed in 1957, made the inland port city a terminal for oceangoing barges carrying local agricultural products, especially grain and fruit.

The US explorers Lewis and Clark camped at the site of the city in 1805, when it was still an American Indian trading place. River rapids here, later submerged by the dam's backwaters, reminded early French explorers of drainage troughs (dalles), and thus the city was named. The Dalles was the last stop on the overland Oregon Trail; pioneers boarded boats here for Portland.