Washington State Route 506

SR 506 begins as the continuation of Morse Street at the Second Street intersection in Ryderwood, a community located in the Campbell Creek valley in northern Cowlitz County. Traveling north to exit Ryderwood, the highway crosses Campbell Creek and enters Lewis County. The street is named 7th Street after crossing Olequa Creek; Traveling east through Vader, 7th Street intersects the West Side Highway, formerly until 1991, and leaves the city heading northeast, paralleling the Cowlitz River, to cross Lacamas Creek, the busiest segment of the highway at a daily average of 1,800 vehicles in 2008. The roadway crosses Bear Creek near its confluence with the Cowlitz River and interchanges (I-5) southbound exit 59; the route turns north to interchange I-5 again at exit 60 in a full diamond interchange. Exit 60 is also the western terminus of the Toledo-Vader Road, formerly until 1991. ==History==

in 1951.|alt=Secondary State Highway 1P (1937-1964), which preceded current SR 506 (1964-present), seen on a topographic map of Hoquiam, Washington produced by the United States Geological Survey in 1951; the road followed the Longview, Portland and Northern Railway until 1953. SR 506 was established in 1964, The rail line, established in 1922 by Longview's founder, Robert A. Long, was completed in 1929. In 1953, the rail line was removed, and in 1963, SSH 1P was shortened and moved west to the newer US 99 freeway, later (I-5). During the 1964 highway renumbering, SR 506 was created, ended in Vader and ended at the I-5 / SR 506 interchange. An extension of the highway connecting Vader to SR 407 near Cathlamet was studied by the state legislature in 1973 but was not recommended for construction. The board ultimately decided in 1992 to recommend that the highway remain under state control. The overpass carrying SR 506 over I-5 was closed on July 6, 2021, after a truck struck it and caused major structural damage. Governor Jay Inslee declared a state of emergency and approved funds to replace the entire bridge. The replacement is scheduled to be completed in late 2022. ==Major intersections==

{{WAint {{WAint {{WAint {{WAint ==References==