When 4,000 or so runners stride through Petaluma Saturday on their way from San Francisco to Calistoga, several will be running through their home town.

Although many run for the competition, most of the runners from Petaluma will run just for the joy of running with friends. "I run for the social aspect," says Nichole Giacomini who is captain of the Tag You're It! team. "It is a lot of fun."

The Ragnar Relay Napa Valley begins Friday at Golden Gate Park in San Francisco and continues through the night. Competitors, working as relay teams, run through the Napa Valley, finishing in Calistoga. Along he way, they will pass through Sausalito, Mill Valley, Kentfield, Petaluma, Santa Rosa and Sonoma. Runners will start in 15-minute intervals, based on their estimated times and are expected to stream through Petaluma sometime around noon Saturday and continuing through the afternoon. The nearly 4,000 runners represent 400 teams who will attempt to complete the 199.2-mile course. Each team member will run three legs of between 13 and 20-plus miles depending on their individual capacities.

Part of the fun for participants is their crazy dress that extends to the teams' decorated support vans. Almost any kind of dress for both runners and vans is fair game, according to Genene Pedrotti, who is captain of the Lagunitas Beer Chicks.

The Beer Chicks, for the last two years, have finished in second place in their division, and Pedrotti hopes to find a different inscription on the trophy she has found on her porch at the finish of the last two races — the one that reads "Almost First."

Pedrotti says it was Jim Jacobs, director of events at Lagunitas Brewery who gave the team its unofficial motto — "Beer drinkers with a running problem."

On the Lagunitas team from Petaluma, along with Pedrotti, are Beth Street, Lisa Stratos, Kellie Delario and Adair Plressas.

For the Chicks, the race is about fun, but theys do take their cause seriously. They will be running for KEEN, a national nonprofit that provides one-to-one recreational opportunities for children and young adults with developmental and physical disabilities at no cost. to their families and caregivers.