There are so many sites in CA. I will recommend some of the sites that we visited. Just north of San Francisco near Santa Rosa is a winery called Korbel Winery, located in the historic Russian River Valley. I know..a winery? The tour is wonderful and filled with history on the area. Much to do about logging and how the area became what it is. Right near the winery is a Redwood forest called Armstrong Woods State Reserve. After those two you could take a short ride to the coast and travel down the coast. We stopped at one of the beaches (see attached) and climbed down the protruding scenic rocks. A little way down the coast from there is Bodega Bay (the town where 'The Birds' was filmed). We did all this in a day.
Another site I recommend near San Fransisco is Muir Woods.
http://www.visitmuirwoods.com/
This is another redwoods site. Actually, it is a lot better than Armstrony Woods. We loved it.
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