Distance from S.F.: 121 miles.
One good way to know you're in a tiny town is if the elevation exceeds the population. Philo — elev. 331 — somehow manages to retain the feel of a hamlet even though it's home to 349 souls, however. This beautiful bend in the road in inland Mendocino County, three hours north of San Francisco on Highway 128, can be a rainy place in the winter. But it comes alive in the summer, especially at the Madrones, a complex of tasting rooms and guest quarters that's neither a hotel nor a B&B but rather a working winery with sleeping accommodations (as well as Stone and Embers, Chef Patrick Meany's intimate restaurant). It's a great place to do absolutely nothing, but summer events like the Barrel-Tasting Festival and the Not So Simple Living Fair draw plenty of city dwellers to the area. Plus, can you ever really get tired of smelling redwoods?
Bonus add-on: Boonville, a slightly larger hamlet a bit further south on 128, is home to the Anderson Valley Brewing Company and its famous sour beers (plus a disc-golf course).