Tualatin Valley

The Tualatin Valley is a farming and suburban region southwest of Portland, Oregon in the United States. The valley is formed by the meandering Tualatin River, a tributary of the Willamette River at the northwest corner of the Willamette Valley, east of the Northern Oregon Coast Range. Most of the valley is located within Washington County, separated from Portland by the Tualatin Mountains. Communities in the Tualatin Valley include Banks, Forest Grove, Cornelius, Hillsboro, Aloha, Beaverton, Sherwood, Tigard, and Tualatin.

In the early 19th century, the valley was inhabited by the Atfalati, a hunter-gatherer Kalapuyan band that spoke a dialect of Northern Kalapuyan. In the middle 19th century, the Atfalati lived in several villages in the valley, including Chakeipi . Early Euro-American settlers called the valley the "Twality Plains", a corruption of the name of the Atfalati tribe. Other early variations included Falatin, Nefalatine, Twalaity, and Quality, with each roughly translated as slow river to describe the Tualatin River, or may translate as land without trees.

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