MP: 26.00 Location: S Seattle, at north end of Marginal Fwy Reassurance shield after the JCT with SR 509   MP: 24.56 Location: S of Des Moines Memorial Dr Exit in Tukwila   MP: 23.76 Location: North of Tukwila Int’l Blvd exit “SR 99” exits, but SR 99 doesn’t really exit. It actually ceases to … Continue reading State Route 99, SR 509 to SR 599