There’s no event that captures the spirit of San Francisco quite like Bay to Breakers. It’s essentially a costumed bacchanal masquerading as a footrace, with entire neighborhoods transforming into street parties, complete with sidewalk DJs and chefs slinging elaborate sandwiches inspired by House of Prime Rib.

As is the tradition, Sunday’s event began with a ceremonial tortilla toss at the starting line near the Embarcadero and ends at Ocean Beach. Although the morning was bright and sunny, high winds were forecast, worrying those more concerned with their race times than their costumes.

At its height in the 1980s, the race drew 110,000 participants, setting a Guinness World Record. Last year attracted a fraction of that — 16,700, however that doesn’t count the thousands of “runners” who treat the event as less of a 12K run and more of like an excuse to celebrate in the streets. The route through the heart of San Francisco requires shutting down lots of major traffic arteries, so be sure to consult our roadmap if you’re traveling throughout the rest of the day.

Although some people do take the race component seriously — and were sorely disappointed by a lack of medals last year — it’s the race’s oddball traditions and anything-goes attitude that has made it one of San Francisco’s signature events. Fantastic costumes are the hallmark of Bay to Breakers, however there’s many runners who take it as an opportunity to run without any clothing at all. Iconoclasts in salmon costumes run upstream. “Centipede teams” connected by bungee cords have their own competition category. And the last liquor store along the route, New Star-Ell Liquor on Divisadero, becomes the busiest shop in town.

Longtime SFGATE staff photographer Douglas Zimmerman is on the race route capturing the race in all of its wacky glory, scroll down to see the best photos from this year’s event.