Just got back from a little jaunt in southern Henry Coe, entering from Bell Station. What an amazing park this is - rugged Mediterranean scrub forest in the Diablo Range, and huge. The tarantulas won't be out for another couple months. The Bell Station/Dowdy Ranch access only opened 2 years ago and there was still nobody there. Get in there before the CA State parks are closed on Labor Day.
It's worth pointing out that the state has tried to put a bullet train through Coe - specifically through Orestimba Wilderness, which is (so far as I know) only one of two wilderness areas on the coast, and certainly the closest to the Bay Area. I voted for the bullet train in the last election (Measure 1A in Nov '08) but it doesn't have to go through Coe. I don't know much about the status of this route and would love for readers to comment and let me know where it is, since I know there was already a good bit of resistance to previous plans.