This is how 420 became ‘Weed Day’

April 20, or 420, is known as “Weed Day” in some circles because the date corresponds with a numerical code for marijuana.

So how did the number 420 come to represent smoking pot? Let’s talk about all the rumors:

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The legend of the California penal code

Some say the number is drawn from the California criminal codes used to punish the use or distribution of marijuana, but the state’s 420 code actually applies to obstructing entry on public land. But this rumor sounds a lot like ...

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The legend of the police radio code

Neither the LAPD nor the NYPD even have a code 420. San Francisco police have one, but it’s for a “juvenile disturbance.” Moving on.


The legend of the Dylan song

This one is a nod to Bob Dylan’s song “Rainy Day Women #12 & 35,” and its lyric, “Everybody must get stoned.” Multiply 12 by 35 and you get 420. Seems like a stretch, though. The story that seems most likely is ...

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The legend of the Waldos

Chris Conrad, curator of the Oaksterdam Cannabis Museum in Oakland, Calif., says 420 started as a secret code among students at San Rafael High School in Marin County in the 1970s who called themselves “the Waldos.”

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They often met at 4:20 p.m. to get high. Their code eventually spread — possibly via Grateful Dead followers — across California and beyond. It’s even the number of a California Senate bill that established the state’s medical marijuana program.

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“420” can now be seen on T-shirts, in online dating-site bios and throughout pop culture. And, of course, on the calendar every April.

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