One of my greatest regrets is not taking the trip on PCH when I lived in California. One of the places I'd like to visit on that trip would be Big Sur on the Central Coast.
This part of the coast offers stunning views as it is a large region where the Saint Lucia mountains suddenly rise from the Pacific Ocean. It is located in Monterey county between Carmel and San Simeon which makes it quite ideal for any road trip.
Big Sur is well know for outdoor activities like hiking and camping, looking at whales or grey condors, a little surfing, or its active bohemian artistic lifestyle.
Have a great day!