American Holiday suggestions.

Snap

think about what you like: city, beach, countryside, museums, bars etc. California has all of those, and some of the best in the world.

Don't try and pack too much in and accept that you can't do everything. If you go to Yosemite, remember its a 350 mile round trip from SF, and if you are going there, you will need to pack walking stuff, boots etc.

Distances between places are pretty significant. Trains in US are crap and expensive, so it may well be worth considering hiring a car instead, or using a bus. Flights are cheap too. E.g we flew from NYC to Boston last year and it was about 45 quid each, one way.

LA - as has been said, its a massive conurbation. A lot of variety and stuff to experience, much more so than SF or SD which are a lot more compact.

Santa Cruz looks like a good place, so we are staying there on our trip next year, for a night, on the way down from SF, which is where we are flying in to.

We really liked Santa Monica/Venice, so are finishing the trip with a week there. We like the feel of the place. Its got good bars and restaurants, has that beach culture to it (the beach is massive), and then you have the alternative, more gritty, trendy and quirky Venice which is a heck of a place. Venice boardwalk is something else. You have the Canals, which are like a calm oasis,

Also there is a 20 odd mile cycle trail along the beach, which is all flat and takes in some lovely views. Downtown LA is 13 miles or so away. But can take not far off an hour to drive as traffic is heavy in and around LA. We drove around the canyons, Bel Air, Beverly Hills - wow, some seriously flash places. Then you have the whole music scene in LA, where you can see a good band somewhere every night.

Tbh, wherever you go, it will be great.

Shrews

Typical journey on the LA freeways below:

KKJale

In SF I didn't find Chinatown all that rough - though it's fairly attraction-free, it's conveniently situated just north of Market Street (the main drag dividing the hilly north from the flat south), and not a bad starting point for exploring in any direction. I like the Mission district best but probably wouldn't stay there, same for the Tenderloin (reputed to be the worst bit). Beware.... in SF there can be a mere $20 difference between a nice clean family-type hotel and a scary place with syringes in the stairwells. Choose carefully! Love the place, though. But 4-5 days max.

If you can, definitely drive from SF to LA down spectacular Highway 1, staying in Santa Cruz for a night or even two. Nice place. Heading south is the best way to do Highway 1, as when you pull over you're on the seaward side. It's hard to find any halfway affordable accommodation in the posh and beautiful coast between Monterey and San Luis Obispo though, so do that in one hit. 

In LA, I'd second choosing Santa Monica for two or three days. Been there many times. Venice is fun and just half an hour's walk down the beach, but down there the seafront isn't safe after dark. Santa Monica IS safe... almost a mini-statelet with a tough police force (don't jaywalk whatever you do). It's got enough bars and restaurants and cinemas and guitar shops for a chilled-out time. 

Never tempted to do Vegas. Ugh!

strtdv

My brother airb'n'b'd it when he was there

Jalapeno

Highway 1 is awesome.

If you do want to spend time in Big Sur I'd recommend booking a cabin in Julia Pfeiffer Burns State Park - beautiful place.

And, eat at Nepenthe in Big Sur (on Hway 1), the sunset above the clouds is spectacular