When first posted as such in 1964, SR 510 started at I-5 Exit 107 in Lacey and followed Pacific Ave, other roads, and the Yelm Highway to Jct SR 507 in Yelm, where SR 510 ended. 1967 moved the western terminus of SR 510 to the Hawks Prairie area. SR 510 now follows Marvin Rd from Hawks Prairie to a junction with Pacific Ave east of Lacey. Since the completion of I-5 in the Hawks Prairie area in 1968, I-5 Exit 111 has been the western terminus of SR 510. Today, SR 510 is 13.08 miles long.
Before 1964, SR 510 had been SSH 5I.
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