Salmon River Highway

Oregon Route 18
Route information
Maintained by ODOT
Length:	52.78 mi (84.94 km)
Existed:	1932 – present
Component highways:	Salmon River Highway No. 39
Major junctions
West end:	US 101 in Otis Junction
	OR 22 in Valley Junction OR 22 near Willamina OR 99W in McMinnville
East end:	OR 99W near Dayton
Location
Counties:	Lincoln, Tillamook, Polk, Yamhill
Highway system
Oregon Highways Interstate US State Named Scenic ← OR 11 OR 19 →

Oregon Route 18 Business
Location:	Willamina–Sheridan
Length:	8.56 mi (13.78 km)
Existed:	1957–present

Oregon Route 18 is a state highway that runs between the Oregon Coast, near Lincoln City and the Willamette Valley, near Dayton. OR 18 traverses the Salmon River Highway No. 39 of the Oregon state highway system, named after the river alongside its westernmost segments.

OR 18 begins (at its western terminus) at a junction with U.S. Route 101, a few miles north of Lincoln City near Otis Junction. From there it winds eastward though the coast range along the Salmon River, past Rose Lodge and through a stand of timber known as the Van Duzer Corridor. Emerging from the coast range, it enters the fringes of the Willamette Valley in the community of Grand Ronde. It is briefly joined by Oregon Route 22 at a location known as Valley Junction, and overlaps OR 22 in a four-mile (6 km) stretch between Grand Ronde and Willamina, at which point OR 22 heads southeast towards Salem and OR 18 continues northeast towards the Portland area. Also in Willamina, a business route veers off to the north to serve the cities of Willamina and Sheridan; east of Sheridan the business route rejoins the mainline. This business loop was the former route and highway until 1957, when the current Oregon Route 18 was built as a bypass.

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Wikipedia