Assuming their flights into town weren't canceled or their buses don't get stuck a rainstorm, as many as 30,000 people opposed to a woman's ability to terminate her pregnancy will descend upon and walk through San Francisco in the 11th annual event known as the "Walk For Life."

Now a full weekend of events held mainly at various Catholic churches across San Francisco (their schedule can be found at the website located at walkforlifewc.com), the centerpiece activity is their "rally and march."

After a Civic Center rally at 12:30 p.m. Saturday, at 1:30 participants will hoof it "from Civic Center Plaza via Gough Street to Market Street and to Fremont Street," according to the SFMTA.

"The march may not completely clear of Market Street until 3:30 p.m.," the MTA warns.

Because of the march, Market Street will be closed between 10th Street and Fremont Street from 1 to 3:30 p.m. Saturday, and "cross traffic between gaps in marchers will not be allowed." "Significant delays" for drivers, all surface Muni routes, and cyclists are expected all along the route.

In years past, the event has concluded with another impromptu rally at Justin Herman Plaza. However, according to event organizers "Due to the presence this year of the ‘Super Bowl City,’ which is under construction on the day of the Walk, we won’t be able to end at Justin Herman Plaza."

But be warned: After the demonstration, don't expect the crowd to just disappear. Instead, they're encouraged to descend on Rincon Park, the Ferry Building, and (of course) Fisherman's Wharf. From their website:

After the Walk ends, we invite Walkers to proceed 4 blocks east to Rincon Park on San Francisco’s waterfront. There you will be met by Mariachi Real de San Pablo, the Walk’s traditional mariachi band. Here you will be able to relax, meet up with friends, take group pictures and enjoy beautiful views of the Bay. There is a walking path along the waterfront from Rincon Park to the Ferry Building, where you can enjoy a number of food shops and other attractions, or even walk another mile to Pier 39 (Fisherman’s Wharf) and its attractions. For a quieter, more reflective time, proceed south on the Embarcadero along the walking path for beautiful views of the bay, the Bay Bridge, and Oakland.