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What Does 420 Mean?

420 tour

You’ve heard 420 referring to pot, but what does it mean?

Undoubtedly you’ve seen the number 420 in reference to weed, but what is its significance, and why did the number 420 become synonymous with pot?


As tour guides conducting cannabis farm tours of pot farms in California’s Mendocino County in The Emerald Triangle, we introduce tourists to California cannabis culture, and give them an in-depth look into the history of weed in the place where it all began and it’s all still happening!   Our guests include everyone from weed farmers, cannasseurs, cronisseurs, and ganjiers to the simply canna-curious, and even people who don’t partake at all, but have gone on all the various tours SF has to offer, and want a truly unique experience in one of the most beautiful regions of Northern California on a 420 tour, visiting Mendocino farms, simply to learn about the history and lore of this long secretive part of Northern California culture.  Our weed tours are for everyone, whether they smoke weed or not, and we give people a look into the real history of cannabis, separating truth from fiction.  So, in that spirit, here’s the real story about where 420 comes from.

Guests explore cannabis farm

For years we’ve been providing weed tours to the public – our season begins on 4/20

There are, of course, a lot of apocryphal stories and urban legends about where 420 comes from.  Let’s get those out of the way first:


“420 is a police code for marijuana smoking”, as in “We have a 420 in progress” – No such police code exists.


“There are 420 chemicals in weed” – Cannabis has hundreds of chemicals, cannabinoids, terpenes, etc, but there aren’t specifically 420 chemicals in the plant.  So far, researchers have discovered over 500 chemicals in pot.


“4/20 is the anniversary of Bob Marley’s/Jimi Hendrix’s death” – Neither Bob Marley nor Jimi Hendrix died on April 20th.


“4/20 is the ideal day to plant pot” – That would be too early.  Weed farmers in Northern California growing full term plants outdoors tend to plant in late May or even early June for an October harvest, as dictated by the natural life cycle of this annual plant.


“It comes from Bob Dylan’s song, Rainy Day Women #12 & 35, (aka Everybody Must Get Stoned), because 12×35 is 420” – The math is right, but the story is false.


So what’s the true story?


The year is 1971 – San Rafael, California, in Marin County, just north of San Francisco across the Golden Gate Bridge.  A group of stoner students at San Rafael High School known as The Waldos, because they used to hang out smoking weed, sitting atop a short wall at the school, near the statue of French Chemist Louis Pasteur.

The Waldos standing in front of the statue of Louis Pasteur at San Rafael High

The Waldos standing in front of the statue of Louis Pasteur at San Rafael High,where they met at 4:20 each day to get high and go on their treasure hunt

One day one of The Waldos got word of an abandoned secret marijuana grow in the Marin Headlands, a national wilderness area just north of The Golden Gate Bridge, started by some Coast Guard cadets who got cold feet.  He had a treasure map of sorts, drawn up by one of the cadets, showing the general area of the grow was, and The Waldos were determined to find it.


Every day they would meet after school, or more accurately, after detention, at the Statue of Louis Pasteur to get high and go on the hunt for the grow.  As they’d pass each other in the halls during the day, they’d knowingly nod to each other, and say, “Louis, 4:20!”  Eventually, they shortened it to just “420”.


They never found the mythical grow, but 4:20 became their sort of “tea time” for smoking pot.


How did an obscure high school pot smoking ritual become world famous?


One of The Waldos got a gig working as a roadie for Phil Lesh of The Grateful Dead, who also lived in Marin County.  The Dead soon picked up the habit of smoking weed every day at 4:20, and before long Deadheads started picking up the habit as well.


On December 28th, 1990, a group of Deadheads from Oakland, California decided to make April 20th a tokers’ holiday, and they printed up flyers inviting people to light up on 4/20 at 4:20 pm, creating the special holiday dedicated to imbibing herb.  Steve Bloom, a reporter for High Times Magazine, got a hold of one of the fliers at a Dead show, and printed the flier in the magazine in 1991.  Since then, 420 has become a universal shorthand for pot, and April 20th has become the official stoners’ holiday.

High Times Magazine 420 cover

High Times Magazine turned the world on to imbibing on 4/20 at 4:20

That’s the true story of where 420 comes from.  


It also happens that 4/20 is the day we officially begin our 2022 tour season.  We’re partnering with Gray Line for a special weed and wine tasting tour.  Besides growing the best pot on the planet, Mendocino County, which borders Sonoma County, also boasts award winning wineries.  Seats are limited, but you still have time to book your tour, and spend 4/20 with us!


Or you could go on a treasure hunt. 


Somewhere, out in the Marin headlands, those cannabis plants may have been growing wild and reproducing for the last 51 years.  Who knows how many plants could be out there by now?

the Marin Headlands

Could that grow still be out there in the wilderness of the Marin Headlands, reproducing and growing every year for the last 51 years?

Louis, 420!