San Francisco rallied against Proposition 8 (the same-sex marriage ban) starting at 10:30 a.m. Saturday morning. The demonstration is part of a slew of other Prop. 8 protests taking place across the United States. From Alameda to Fresno, New York City to Stockton, Los Angeles to Redding, this large scale Join the Impact: National Protest Against Prop. 8 effort promises to be a big one.

Check back for more images throughout the day. And if you have some shots you would like to share with SFist readers,. feel free to send them here.

Update I: A gaggle of protesters blocked the Octavia off-ramp resulting in several arrests.

Update II: "Thousands of demonstrators" showed up for today's (unusually warm!) demonstration.

Update III: A success. Great job, folks. (We'll have pics from the marches that sprouted from Civic Center rally later tonight.) Be sure to check out today's civil rights scene in Seattle, LA, Boston, and Austin.