For the best review on getting into town from over 100 airports around the world, check out:

www.concierge.com/travel/c_planning/06_airports/intro.html

As for SFO, if you arrive during the work day, the CalTrain runs often. If it is the weekend, I would wait for the city bus. Avoid the shuttle services as these take longer and equal the cost of 2 or more people sharing a taxi to downtown. Or you could do what I did, rent a car at the airport and drive around all day and turn in the car at night at their downtown Union Square location. No overnight parking fees and $30 paid including taxes for weekend rate covered driving around San Francisco. And believe, there is no city more fun than driving the hills of downtown SF!


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"Fly me to the moon and let me earn alot of miles."