 SR 433 enters Washington and Cowlitz county on the National Register of Historic Places listed Lewis and Clark Bridge over the Columbia River. The highway travels northwest along the bridge for 0.54 mi (0.87 km) before dropping into the city and Port of Longview, intersecting the access road to the Port, Port Way. The highway continues north, paralleling railroad tracks belonging to the Columbia and Cowlitz Railway, intersecting Port Way again, and gaining one lane in each direction for a total of four lanes before the highway terminates at an intersection with SR 432 and Industrial Way. The highway has a posted speed limit of 35 miles per hour (56 km / h) for its entire length. Oregon Way continues after the end of SR 433 into downtown Longview and SR 4.
