Taking public transit was encouraged to help reduce air pollution. As part of that, riders were able to ride the ferry in the San Francisco Bay for free.
A dose of natural air conditioning might be just what the doctor ordered amid a rare October heat wave.
"You don't need air conditioning. You don't get that kind of weather here," said Paul Wilson, a Richmond resident.
Passengers on board the Richmond ferry heading to San Francisco didn't pay a dime, all to soak in views that people travel from across the world to see.
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"The idea today is knowing that we all have power in our individual actions, and we can advocate to government as well, and it's really a job we can do 365 days a year," said John Gioia, a Contra Costa County supervisor and co-chair of the Bay Area Clean Air Day.
Gioia said as part of California Clean Air Day, the San Francisco Bay Ferry was offering free ferry rides across all routes all day on Wednesday.
"Once you get hooked on transit, especially the ferry, you may end up taking it more frequently or even trying it on the weekends instead of driving into San Francisco for a fun day in the city," he said.
With San Francisco on its third excessive heat warning day this week, it coincidentally happened to fall on a Spare the Air day too.
Meaning, people across the Bay Area are urged to reduce air pollution by working remotely, walk, bike, carpool or take public transit.
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"I think this is great that the ferry, today, especially because we just got into Indian summer, so it's great day to be out. I mean look at this. This is a fantastic day to be out on the Bay," Wilson said.
It was something Wilson said was no better way to celebrate his birthday.
"I've been doing months since 700 and today I turned 840 months." he said.
As part of California Clean Air Day, you can also take the "Clean Air Pledge" right now on what you plan to do to clear the air. That's available here.