In 1964, SR 500 started at Jct I-5 in Vancouver and headed east to Orchards. The route originally followed Fourth Plain Blvd. SR 500 moved to an expressway that was built in stages between the mid 1970s and mid 1980s from I-5 to Orchards. From Orchards, SR 500 heads east and then south to Camas. The eastern terminus of SR was originally at Jct US 830 in Downtown Camas. A US 830 expressway was built to the south of downtown in the mid 1960s and SR 500 was extended to the new expressway. In 1968 US 830 was redesignated as SR 14. Today, SR 500 is 20.35 miles long.
Before 1964, SR 500 had been SSH 8A.
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