The following recommendations I have given friends from outside northern California who were planning a vacation here.  Northern California Best Places has a lot of other ideas, though it’s a out of date now. These days you can get a “look” at many places through Google Street View, and if it’s not, maybe the SF virtual tour will have it.

Transportation

Your first and last day will most likely involve an airline flight and transportation to/from the airport. The San Jose Airport (SJC) is a smaller airport which I have found typically is the easier to get in and out of. The San Francisco Airport (SFO) is the largest airport and typically has the larger number of flights to any given destination. Sometimes fares out of Oakland Airport are cheaper than SJC or SFO.  Relative to Mountain View, SJC is 20 minutes, SFO is 45 minutes, and Oakland is around 60 minutes. It is possible to get to Mountain View from SJC via Light Rail (though it’s slow), or from SFO via CalTrain. A taxi/uber/lyft will typically be around $25 from SJC, and around $50 from SFO.

Areas to Explore

Most people think to visit the typical tourist stops such as Chinatown, Pier 39, the Golden Gate Bridge, etc.  Make sure to visit some of the incredible parks in the area.

Whenever I have friends visiting for a more than a few days I typically recommend: getting up to see Muir Woods, checking out a couple of SF neighborhoods like Haight-Ashbury and whatever museums would be loved. If Muir Woods isn’t visited going to Henry Cowell State Park is a must for the redwoods. I highly recommend the scenic drive down to Big Sur, checking out Point Lobos State Park, and the town Carmel by the Sea. More detailed options:

• North of SF: Drive to Muir Woods (need reservations, parking bad), Muir Beach, Marin Headlands, Sausalito. This could full a whole day or be trimmed down and combined with SF.
• San Francisco: culture, museums, food, parks. 1-3 days.
• Santa Cruz and Coastline for redwoods, butterflies, sea lions, beaches
• Monterey Penisula & Big Sur: picturesque coastlines, world class aquarium, good food and art boutiques.
• Other info general SF Bay Area and Mid-Penisula

When people have extra time or specific interests

• Napa Valley & Wine Country: Wine! Food! 1-3 day
• Yosemite: One of the most spectacular parks in the world. You should spend at least three days and visit the Valley floor, Marapoa Grove,  and Tuolumne Meadows. 3-4 days.
• Tahoe: Tahoe is pretty… but unless you have a lot of time, I would skip Tahoe so you have more time as Yosemite. 3-4 days.
• Northern Coast / California Redwoods: If you have another 3-6 days, head north of San Francisco. There are a number of cute towns along the coast, and the wonderful Redwood State & National Parks region just below the Oregon border.