On a cool, overcast morning Thursday, thousands of Sonoma County commuters shunned their cars and hopped on bicycles to promote physical and environmental health on Bike to Work Day.

The 20th annual event, celebrated across the Bay Area as part of a month-long biking campaign, drew dedicated cyclists dressed in spandex on pricey road bikes as well as commuters in suits on comfy cruisers with bulging panniers.

They gathered at the more than 20 energizer stations around the county to fuel up, listen to music and talk about cycling.

“It’s a good scene,” said Lisa Ludwigsen, marketing team leader at Whole Foods. “Everyone is out having fun and being healthy.”

Ludwigsen handed out fruit, juice, coffee and bagels at a booth sponsored by Whole Foods and Kaiser Permanente at Walnut Park in Petaluma.