This area extends from the north side of Corvallis (in Benton County) to a few miles north of the northern border of Polk County. The Willamette River forms most of the eastern boundary, and the western boundary is a few miles west of Falls City. It excludes McDonald and Dunn Forests.
Most of this area is in Polk County. The major towns are Dallas (the seat of Polk County), Falls City, Independence, Monmouth (the home of Western Oregon University), and West Salem.
Notable places include two national wildlife refuges (Ankeny and Baskett Slough), a state wildlife area (EE Wilson), Sarah Helmick State Park, Luckiamute Landing State Natural Area, and the Buena Vista Ferry. There are numerous wineries in this area, and portions of the Willamette Valley American Viticultural Area lie within this area.