Known as one of the best transportation systems in the world san franciscos bay area rapid transit bart will get you to your destination quickly and easily book online now so you dont have to wait in line at the airport purchase a voucher redeemable for a 20 bart ticket your 20 bart ticket will have enough value for a round trip bart ride from sfo to downtown san francisco downtown oakland or downtown berkeley plus a small balance you can easily upgrade for round trip travel to east