Cannabis and 420: Why is this number so significant in the history of marijuana?

The importance of the number 420 with cannabis

Global marijuana day, 420 and cannabis: why the marijuana holiday exists

If you have opened this article, it means that you are one of those curious people who would like to know the relationship between cannabis and the number 420, am I right?

You’ve probably heard and read about all sorts, leading to more confusion.

So, in this article, we will see the real origin of 420 and why cannabis is celebrated every year.

Demonstrators on 20 April Cannabis Day

420 cannabis: dispelling some myths about the symbolism of this number

20 April, or 4/20, is known as ‘weed day’ or international marijuana day.

But how did the number 420 come to represent the smoking of marijuana?

First of all, let’s dispel some myths.

1. The California penal code legend

Some claim that the number originated in California’s criminal laws to punish the use or distribution of marijuana. But state code 420 refers to obstructing entry into public space.

So that’s not precisely the reason.

We continue.

2. The legend of the police station code.

Neither the LAPD nor the NYPD has a 420 code. The San Francisco police have it, but it is used for juvenile disturbances.

3. The legend of Bob Dylan’s song

This myth refers to Bob Dylan’s song Rainy Day Women #12 & 35 lyrics: ‘everyone should get high’.

If you multiply 12 by 35, the result is 420.

It seems a bit of a stretch, and in fact, Dylan has never confirmed any link between the song and the date.

So the most likely story, it seems, is the Waldensian legend.

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Waldensian legend explains why 420

According to Chris Conrad, curator of the Oaksterdam Cannabis Museum in Oakland, California, 420 originated as a secret code among high school students in the early 1970s.

It all started in 1971 in San Rafael, a city in northern California.

One day, a group of teenagers calling themselves ‘the Waldos’ came across a hand-drawn map pointing to an exact spot in Point Reyes, northwest of San Francisco, where marijuana growing was supposedly hidden.

Without hesitation, the students decided to trust the mysterious coordinates and set a time to go in search of the plantation: 4:20, just outside the school.

They drove 45 minutes to the site, but when they arrived, they found no crops.

However, they kept ‘420’ as a secret code for cannabis, which they smoked ‘too much at the time. As one of the members of this group, director Dave Reddix, also known as Waldo Dave, who is now 67, was admitted decades later.

But why precisely 4:20?

For them, that time was ideal: it was the end of school, and the parents had not yet returned home, so it became a code to use in front of unsuspecting parents.

From there 420 spread, perhaps through the followers of the rock band Grateful Dead, throughout California and beyond.

In addition, 420 is the number of the Senate bill establishing the state marijuana programme.

420 cannabis

420: How Global Marijuana Day is celebrated today

The number 420 has become increasingly popular among marijuana users, so much so that it has become part of the symbolism of the famous rock band Grateful Dead, through the group’s fans, the ‘deadheads’.

In 1990, Steve Bloom, who was working as an editor at the marijuana magazine High Times, received a flyer from the Grateful Dead explaining the significance of the number 420.

From then on, the group began using that code for everything, even for holding editorial meetings, according to the BBC.

Although the Waldos’ version has some detractors – other groups claim to be the inventors of 420 – the San Rafael group has its evidence and claims it was their idea.

They have their website,, where they tell their story in great detail and display all the documentation that proves they are the originals: letters, school diaries and even the first flag with ‘420’ and a marijuana leaf.

Beyond the disputes over the authorship of the term, the fact is that Global Marijuana Day is celebrated every year on 20 April because it is the 4th month and the 20th day.

On this date, activities are usually held in parks and squares and in some countries, marches are also organised to decriminalise consumption.

Today, 420 can be found in all marijuana-related products and brands, from songs to T-shirts, hats, bags, pins, consumer items and even memes.

In fact, cannabis users tend to consume at 4:20 in the afternoon.

As a curious fact, devotion to the number has gone so far that authorities on Interstate 70 in Colorado had to change the 420-mile sign to one that reads 419.99.

They were tired of having their sign stolen and replacing it so often.

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In this article, we have looked at the origins of 420 and how it is celebrated worldwide today.

We debunked some myths and tried to reconstruct the history of Global Marijuana Day to the present day.

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