From KQED.

If you live or work in San Francisco, you likely hear this sound every Tuesday at noon. It's a sound with its own yelp page.

average rating. It's a sound with its own yelp page. Average rating, four stars. Here are some of the reviews.

It was late morning on a Tuesday when I was eating lunch with my friend and her kids at the cheesecake factory in Union Square.

When the noon siren went off, all the tourists of my friend looked alarmed like,

uh, what's happening? Is the city falling down?

When I'm feeling nostalgic for the olden days of air raid sirens and a bomb drills,

I take comfort in the The Tuesday noon siren has become its own sort of entity and local character that people

look forward to hearing and even tracking time to.

That's certainly the case for this week's question-asker.

It is my total North Star for when it is Tuesday.

Literally every time it happens, I go,

it's Tuesday at noon.

This is Jennifer Corbel.

She's a native San Franciscan who grew up in the sunset district.

So basically my entire life, I've been hearing this siren.

And for decades, every time she hears it, she's wondered.

When did it really start and how does it work?

I'm Olivia Allen Price.

This is Bay Curious, where we answer your questions about the Bay Area.

Today, the history and mechanics of San Francisco's noon siren.

Support for Bay Curious is brought to you by Sierra Nevada Brewing Company, still family owned, operated, and argued over.

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