U.S. Route 101
The nearly highway's northern terminus is in Tumwater, Washington: the route remains along the Olympic Peninsula's coastal perimeter west, north, and east; the northernmost point on the highway is in Port Angeles. The southern terminus of US 101 is in Los Angeles at the East Los Angeles Interchange, the world's busiest freeway interchange.
U.S. Route 101
US 101 enters Oregon south of Brookings, and is seldom out of sight of the Pacific Ocean except the northern end near Astoria and from Port Orford to Florence other than a viewpoint south of Winchester Bay; with another major exception being a significant inland stretch south of Tillamook, Oregon. It crosses the Chetco River at Brookings, the Rogue River in Gold Beach, the Coquille River just north of Bandon, Coos Bay at North Bend via the McCullough Bridge, named after the engineer who designed a series of bridges built on the Oregon Coast in the 1930s, the Umpqua at Reedsport, the Siuslaw in Florence, Yaquina Bay at Newport, and Youngs Bay and the Columbia River at Astoria. The stretch between Florence and Yachats is considered one of the more attractive segments of this highway. There are at least 86 Oregon state parks along the Pacific coast, including the Heceta Head Lighthouse. There are also many scenic bridges along the Oregon Coast that carry US 101, such as the Yaquina Bay Bridge in Newport. Because US 101 forms the main street of almost all of the coastal towns in Oregon (with the exception of Cannon Beach, Pacific City and a few others), traffic is often congested and slow in the summer months. The highway crosses the mouth of the Columbia River over the Astoria-Megler Bridge at Astoria into Washington, and follows the Columbia downstream to Ilwaco.
Oregon Route 42 (OR 42 and OR 42S have taken over old portions of US 101 around Coquille following a bypass. Reconstructions of US 101 in the post-World War II era shortened distances and eliminated the worst narrow curvy sections in various places on the Oregon Coast.