It is a Labor Day tradition, when serious cyclists, mostly amateurs, get to go high speeds on San Francisco streets.
"It's one of those things that you never want to see disappear from this city," Scott Lowe, CEO of Metro Mint said. "It's been going on for 34 years."
In those 34 years, the Giro to San Francisco has gone from a small-scale event to one with 800 cyclists, and there is a big surge of women training to ride and race. Amateur athletes work full-time jobs, juggle kids and then train for the race.
"We just really try to work together to find time to train in the mornings or get up early and ride the trainer and switch off on the weekends," rider Birgit Cory said.
Cyclists will do laps around the Levi Strauss Plaza area. They will start at Battery and Union Streets and then move along Green, Front, Vallejo and Sansome.
The San Francisco course is not easy, with curves and corners. The race is comprised of short fast sprints, and the road conditions can be hazardous.
"There are a lot of potholes, the first right hand turn the sun was right in your eyes so you couldn't see exactly what you were diving in to," rider Joanna Bechtel said.
Crashes do happen in the race. Jay Robertson is one of the best amateur cyclists in the country and admits the course can get challenging, even for the experienced riders.
Robertson met the challenge last year, winning the race and is the person to beat this year.
Stay with ABC7NEWS.COM for continued updates on the race.