Spring Native Plant Garden Tour

http://www.cnps-yerbabuena.org/gardens/annual_garden_tour.html

Cherry Blossom Festival (in Japantown)

http://www.nccbf.org/

San Francisco International Film Festival

http://www.sffs.org/

Critical Mass Bike Ride (begins at east end of Market St on the last Friday of the month at about 6pm)

http://critical-mass.info/