Before California became the Golden State, it was just one part of the vast and expanding Spanish empire. A key component of Spanish imperialism was spreading Catholicism, and in an effort sponsored by the Spanish crown, El Camino Real-literally the royal road, or more poetically, the King's Highway-began. Along the road, 21 Catholic missions were built in intervals from the first mission in San Diego to the last in Sonoma. These buildings and the route had an immense influence in shaping the state. Present-day cities don't have missions; the cities exist because of them. The King's Highway still defines California, and each of these cities that began with missions is now a vibrant and key part of the state-and conveniently for us pilots, they also have their own airports. Three stops in particular highlight the best of California's central coast and are perfect gateways for aviators looking to explore the King's Highway by air.