What Is 420? The True Story, Surprising Facts, and How It Became Weed’s Biggest Holiday
Forget the myths—here’s how a group of California teens, the Grateful Dead, and a secret grow map helped spark a global cannabis holiday.
Most people know 420 means weed. But how did three random numbers turn into a global symbol for cannabis culture—and an unofficial holiday with its own sales spikes, concerts, and political activism?
If you’ve ever wondered why people celebrate cannabis on April 20—or why “4:20” is considered the universal time to light up—this post breaks it down.
What Does 420 Mean in Weed Culture?
At its simplest, 420 is a code word for cannabis. You’ll hear it in phrases like “420-friendly” (open to cannabis use), “Let’s meet at 4:20” (you know what for), or just a casual nod to April 20 itself.
It’s also become the biggest day of the year for the cannabis industry. Dispensaries roll out major discounts. Events are everywhere. Some brands report 25–30% spikes in sales, and major media outlets cover the celebration each year.
But what’s the origin? And why 4-2-0, of all numbers?
Who Started 420? The Real Story Behind the Term
The most credible origin story traces back to a group of high schoolers in San Rafael, California, in the early 1970s. They called themselves The Waldos, and every day after school, they’d meet at 4:20 p.m. near a statue of Louis Pasteur on campus. Their mission? To find a hidden cannabis grow on nearby federal land.
One of the Waldos had a hand-drawn map to the supposed grow site—passed along by a friend whose brother had abandoned the crop. The Waldos never found the weed, but “420” became their code word for the daily meet-up to smoke and search.
The reason it spread beyond their friend group? One of the Waldos’ dads handled real estate for the Grateful Dead, giving them backstage access and regular contact with the band. The term caught on among Deadheads and crew, then expanded into the larger counterculture. By the time High Times popularized it in the 1990s, 420 had already become a fixture in cannabis slang.
Common Myths About 420 (That Just Aren’t True)
Despite all the rumors, here’s what 420 is not:
It’s not a police code for cannabis possession
It has nothing to do with Bob Marley’s birthday (he was born in February)
It’s not the number of active chemicals in cannabis (there are hundreds, and the number keeps growing)
The real story is simpler—and better. A group of teenagers with a code word, a time, and a mission accidentally sparked a cultural phenomenon.
Why April 20 Became the Global Cannabis Holiday
Because “420” was already shorthand for cannabis, April 20 (4/20) was the obvious choice for an annual day of celebration. Over the decades, 4/20 grew from small smoke-outs to full-scale festivals and political rallies.
It’s not just about lighting up—it’s also about:
Demanding fair access to medical cannabis
Calling for criminal record expungement
Pushing for federal legalization
And creating space for joy, connection, and community
For many people, especially in states where cannabis is newly legal, 4/20 represents a kind of freedom they never thought they’d see.
Strange but True: 420 Facts You Probably Didn’t Know
California passed Senate Bill 420 in 2003 to expand medical cannabis access. Lawmakers leaned into the joke.
Denver International Airport removed Gate 420 because the sign kept getting stolen.
Mile marker 420 signs have been replaced with Mile 419.9 in multiple states.
The Waldos still exist—and they’ve kept physical proof of their story, including letters and memorabilia.
Cannabis companies prep for 420 like it’s Black Friday, with deals, giveaways, and major ad campaigns.
How Cannabis Brands and Dispensaries Celebrate 4/20 Today
420 is now the biggest revenue day of the year for cannabis retailers. Expect:
BOGO deals on edibles, flower, and concentrates
Pop-ups and events at dispensaries
Brand-sponsored concerts and local activations
Huge traffic to online delivery platforms
New product drops from legacy and indie brands alike
But there’s also a growing movement to reclaim 420 from pure consumerism and use it to raise awareness—especially around cannabis injustice and safe access.
Beyond the Haze: 420 and the Push for Cannabis Justice
Behind the parties and product drops is a serious truth: millions of people were criminalized for something now sold legally across the country.
That’s why many cannabis activists use 4/20 as a time to talk about:
Expungement efforts for non-violent cannabis offenses
Access for veterans, seniors, and the chronically ill
Ongoing stigma in housing, employment, and parenting
State-level barriers that still keep people from using this plant safely
Celebrating 420 can be joyful—but it can also be intentional.
Final Thoughts
420 didn’t come from a government agency, a marketing team, or a corporate initiative. It came from a group of teenagers with a ritual, a map, and a plant that brought them together.
Today, it means different things to different people. For some, it’s a party. For others, it’s a protest. For many, it’s a reminder that the cannabis movement has always been grassroots—and still has a long way to go.
If you learned something new, subscribe to Senior Savvy Cannabis for daily insights into cannabis, health, and wellness. When you join, you'll get our free cannabis strain tracker delivered to your inbox to help you find what works best for your body and mind.
Disclaimer: The information provided on this blog is for educational purposes only and is not a substitute for professional medical advice. Always consult your healthcare provider before starting or changing any treatments, including cannabis use.
Of course this only works for USA as the rest of the world is 204, 20 April