On the way to Santa Monica from San Diego we recommend 2 stops:
1ST STOP: San Clemente. Have a breakfast here and go to the beach until noon.
BEAUTIFUL BEACH, very different from the others. It is difficult to park, but you can find some free spots if you get more into the residential neighborhood. There is also a beachfront parking lot in a plaza.
The best recommendation is to simply get lost in the streets, go down to the beach and relax a bit.
2ND STOP: Huntington Beach. You can have lunch right here.
Huntington is in Orange County, so fans of THE O.C can also visit Newport!
If you feel like shopping there are outlets nearby, like Fashion Island (there in Newport).
The beach and the city of Huntington Beach are VERY very nice. It's nice to give the car a break, walk for a while, and recharge batteries to continue towards Santa Monica.
OTHER USEFUL GUIDES