State Route 510 (SR 510) is a state highway in Thurston County, Washington. The 13 miles (20.9 km) long highway extends southeast from an interchange with Interstate 5 (I-5) in Lacey to SR 507 in Yelm. SR 510 roughly parallels the Nisqually River, the border between Thurston and Pierce counties, between the Fort Lewis and Nisqually Indian Community area to Yelm.