The mobile party known today as Bay to Breakers, held in San Francisco on the third Sunday in May, has been run every year since 1912. Here are records and other cool facts about the one-of-a-kind race. See our Bay to Breakers timeline for milestones of the historic race, and get the run-down on registration and best places to watch in our 2015 Bay to Breakers guide..

RACE COURSE: Starts at sea level, along San Francisco Bay (Howard and Beale streets, in the Embarcadero area).

The 7.46 miles (12 kilometers) are largely flat, but at the 2.5 mile mark is the infamous Hayes Street Hill, a five-block stretch that rises 215 feet above sea level. Mostly (and gradually) downhill from there, along the Panhandle, through Golden Gate Park, to the finish line on the Great Highway—and the Pacific Ocean’s breakers.

PARTICIPANTS: At the front of the pack are the serious athletes, usually led by Kenyans and Ethiopians. They’re followed by tens of thousands of runners, joggers and walkers, many in costumes, in various states of un-dress, or linked together as "centipedes." Estimates in recent years have said that up to half of Bay to Breakers participants were not registered for the race (in 2010, then-San-Francisco-mayor Gavin Newsom was among them).

COURSE RECORDS
Men's record - 33:31, by Sammy Kitwara (Kenya, age 22), in 2009.
Women's record - 38:07, by Lineth Chepkurui (Kenya, age 22), in 2010.
Men's Centipede (13 runners tethered together) - 36:44, by LinkedIn, in 2012.
Women's Centipede - 46:36, by Impalas, in 2012.

BAY TO BREAKERS - BY THE NUMBERS

1.75 Million: Estimated total number of participants in the race’s 100-year history.

80,000: Estimated number of spectators, race staffers and volunteers who line the race course on race day.

78,769: Number of registered runners in the largest Bay to Breakers, in 1986 (total number of participants was about 110,000).

99: The age of the oldest known participant, Stefan Arcelona (in 2000).

43: Number of consecutive years that Harry Cordellos, who is blind, has run Bay to Breakers; he says he can identify every pothole on the route.

25: Number of registered runners in the smallest Bay to Breakers, in 1963.

1: Age of the youngest known participant, Robert Rosen (in 2000).

Sources: Bay to Breakers presented by craigslist; Zazzle Bay to Breakers; ESPN; Wikipedia.