After reaching the main entrance to Vandenberg Air Force Base, SR 1 turns northeast, away from the immediate coastline of the base, to join SR 135. Route 135 then splits from Route 1 south of Orcutt, and the Cabrillo Highway turns northwest back towards the coast to Guadalupe. It enters San Luis Obispo County, avoiding the immediate coastline of the protected Guadalupe-Nipomo Dunes, before passing through Grover Beach and subsequently joining US 101 for the third time at Pismo Beach. The US 101/SR 1 concurrency then avoids the immediate coastline of Avila Beach and Diablo Canyon Power Plant, and instead heads straight inland to San Luis Obispo.