The History of 420: From Treasure Map to Global Recognition

Everyone knows 4/20.

It’s on calendars, plastered across promos, and understood without much explanation. Even people who don’t smoke know the number means something.

But the origin? It’s not what most people think. No police codes. No hidden math. No conspiracy-level backstory.

It started with five high school kids, a treasure map, and a very specific time of day.

1971: The Waldos and the Map

Back in 1971, five students at San Rafael High School in San Rafael, later known as the Waldos, caught wind of something interesting. A friend’s brother had been growing cannabis out near Point Reyes.

There was just one problem: He was worried about getting caught.

So, according to the story, he did the logical thing, he handed over a map and gave the group permission to find it. That’s where things start to feel less like a legend and more like a teenage side quest. The Waldos picked a meeting time: 4:20 PM.

Not because it meant anything but because:

• School was over

• Sports practice had ended

• Parents weren’t home yet

It was the perfect window.

They’d meet near a statue of Louis Pasteur on campus, pile into a car, and head out on what they started calling “safaris.” The goal? Find the crop. The result? They never did.

The Code That Stuck

Even though the treasure hunt didn’t pay off, something else did. “420” became their shorthand.

At first, it was just practical:

• “420?” meant are we going?

• “420 Louis” meant meet at the spot

But like most inside jokes, it started to evolve. It became less about the map…and more about the routine: Meeting up. Getting out of the usual rhythm. Doing something that felt like theirs

It stayed small. Local. Personal. Until it didn’t.

How 420 Left San Rafael

The turning point came through proximity. One of the Waldos had connections to Phil Lesh of the Grateful Dead. That’s how “420” found its way into a much bigger circle.

From there, roadie crews picked it up. Fans (Deadheads) spread it, and the phrase traveled with the band. What started as a private code became shared language.

Still underground, but no longer contained.

1990: The Flyer That Made It a Date

Fast forward to December 28, 1990. A group of Deadheads handed out flyers in Oakland. The message was simple: Meet on April 20 at 4:20 PM. No long explanation. No branding. Just a coordinated moment. One of those flyers landed in the hands of Steve Bloom from High Times. And that’s when everything shifted.

Once High Times published the concept, “420” spread nationally. April 20 became the unofficial cannabis holiday and the meaning became widely understood

By 1998, the Waldos were officially credited as the origin. At that point, it didn’t belong to a group anymore. It belonged to anyone who got it.

The Myths

Let’s clear a few things up. There is a lot of confusion surrounding the lore of 420.

One of these is that it was a police code for marijuana. This came about because High Times originally posted about 420 1991, where they stated it was slang for the police, but later confirmed this was an error. Some even say it is related to Adolf Hitler’s birthday or hidden meanings in songs or math. None of those hold up. 

The real story is simpler, and more believable:

 A group of teenagers picked a time, followed a map, and created a habit.