Hi me (21 years old) and my boyfriend (23 years old) are in the process of planning a trip to california for June 08. We have allocated 17 nights for the trip. We have decided to drive from san francisco to san diego spending 3-4 nights in san francisco, LA and san diego. If anyone could suggest places that we must visit along the way between these 3 cities and where we should stopover along the way to break up the trip it would be really helpful. After san diego we will fly to las vegas for 4 nights before we return to the UK.
Thanks

This sounds like a great trip. If you type in San Francisco here you will get all kinds of suggestions about what to see in the city. When you head South...stop first in San Juan Batista for a quick look at the early Calif. Mission and town, then continue on to the Monterrey, Carmel area. Tour the Monterrey Bay Aquarium. Also the mission in Carmel. These missions are a fascinating part of Calif. history and are found aprox every 24 miles along the whole state. Some in ruins, others restored. Go down Route #1 to San Simeon. Its about 90 miles along fantastic coast line of Big Sur..redwoods and mountains. Then visit San Luis Obispo (another great mission) and then down to Santa Barbara (and mission) then on to Los Angeles. If you keep to #1 you will arrive in LA via Malibu and Santa Monica. Others will post about these cities. Enjoy your trip. If you have the $$ in Las Vegas, Try to see the show "O".. AMAZING

Near Carmel, take an hour or so to check out Point Lobos State Park, a small, less touristed park with sea otters and pelicans in the waters! http://pt-lobos.parks.state.ca.us

The drive through Big Sur is terrific. We stayed at Pfeiffer-Big Sur State Park. There are campsites there, but also a lodge (so you don't have to drag a tent with you from the UK - LOL). My visit was a few years ago, but I remember that the food at the lodge was quite good - and we were happy we didn't have to light a fire to get coffee in the morning! (Needless to say, I'm not much of a hardcore camper! We brought tent and sleeping bags in our luggage so we could stay in campgrounds, but didn't do the full-on camping thing.) www.parks.ca.gov/?page_id=570 If you click on the Big Sur Lodge link on the left, then Restaurant at the top, it looks like the setting and menu are still as nice as when I was there...

FWIW, this was a 10-day trip, starting in SF then up to Sonoma (to see relatives), west to Yosemite, east again to Carmel then down the coast, ending in LA.

All the towns that kleroux mentioned are nice walk-around towns even without their missions --- so, Monterey has a "fisherman's wharf", Carmel is a beautiful little town with upscale shopping and dining and a nice beach at the end of the main drag, San Luis Obispo is a wonderful town for wandering/eating for a couple of hours at least, same for Santa Barbara.

Once you get south of LA, of course, there's Disneyland, and Laguna Beach and the other beach towns.

Wow, I am a native Californian, and still envious of a 17 day trip down California! Well, the Monterey/Carmel area is definitely worth a night or two[the Monterey Bay aquarium is, I think, world class], and I believe just south of there is Big Sur an incredible forest that butts up against the Pacific Ocean, also worth a night. From there you could continue heading down Pacific Coast Highway [PCH] and spend a night in the Cambria / San Simeon area. You MUST stop and visit Hearst Castle, really nothing else like it in all of California. From there continue south to Santa Barbara. This is, in my humble opinion, the most beautiful spot in all of California, spend at least two nights here. There are Missions, botanical gardens, amazing hikes, and, if you like wine, a fair bit of wine tasting about 40 minutes north-east from Santa Barbara. If you like to party / people watch, you might check out Venice Beach. In LA, gosh, check out Hollywood, and if you're into art/museums, The Getty is a great, FREE museum where you could spend a whole day.
Down to San Diego, you'll likely want to stay either somewhere near La Jolla or downtown around the Gaslamp District. For sure check out La Jolla, The San Diego Zoo / Balboa Park, and Coronado Island and the Hotel Del Coronado. If you'd like specifics on anything, please let me know, I can go on and on and on...One side note: keep in mind that in the southern-half of coastal California we have what is called "May-grey, June-gloom" where there is a frequent marine-layer, and not so much of the sunshine that we are well know for. It's not a for sure thing, you could certainly come out and have a grand old time, but it might not be sunny and 85* here everyday as some people expect. Of course you can also avoid this by heading 30 minutes or so inland...NWG

as others suggested, you should take the longer scenic route along the coast from SF to LA. you can stop in Santa Barbara, abotu 1.5 hours from LA as well as Monterey/Carmel.

There are plenty of posts of things to do within SF, LA and SD here. So you can run a search for that info.