@Rowyn: Interesting, I did not know that California had its own version of Old Faithful. It’s pretty close so that might be the winner.

@Jason: I have (as far as Carmel), but there’s no reason not to do it again.

If you go north, there’s obviously wine country, which aside from vineyards also includes things like hot springs & geysers, safaris, hot air balloons, and a petrified forest. Further north are Mt. Lassen and Mt. Shasta, and further east is gold country.

If you head south, there’s stuff along the central coast, though it might be cold and foggy at this time of year. Around Monterey Bay there’s Santa Cruz, of course, other things like the Elkhorn Slough, Mission San Juan Bautista, and Point Lobos. Further south there’s Big Sur, then Hearst Castle, then Morro Bay and San Luis Obispo.

I hope you like parks and/or missions, since we have a lot of both in California. Might be worth checking AAA’s VIA Magazine which is all about places to travel in the West.