Today is April 20th – affectionately known as national (and perhaps international) pot smoking day. How did 4/20 come to be? Although we are certainly not the first to ask this question or to even write about it, today we decided to take a light-hearted dive into the origins of this “holiday.” Surprisingly, we found consensus among the History Channel, Time Magazine, the Huffington Post, the LA Times, and High Times magazine on this question. But first, let’s go through the most prominent 420 origin myths:

  • It’s the police code for smoking in progress. While this sounds perfectly reasonable, it is wrong. Interestingly, 420 is the radio code for homicide in both fact (the Las Vegas Police Department) and fiction (CSI).
  • The Grateful Dead—they stayed in hotel rooms numbered 420, didn’t they? A little closer to the truth, but still not accurate.
  • It’s Bob Marley’s birthday or the date of his death—both are incorrect.
  • The number of chemical compounds in cannabis. Although this one has a nice scientific façade, it is just not true. There are reportedly 315 chemicals in cannabis.
  • Tea time in Holland—not it.
  • It came from Bob Dylan’s song “Rainy Day Woman #12 and 35”. Perhaps the most charming of options, and 12 multiplied by 35 does equal 420, but this is still not it.

The consensus seems to be that 420 originated in the early 1970s in San Rafael, California. It was coined by a group of high school students who called themselves “the Waldos” because they liked to hang out in front of a wall and smoke pot. They used “420” coupled with the name of a meeting spot as a code for their activities and the time said activities would take place. The group met in front of the statue of 19th-century French scientist Louis Pasteur (i.e., “420 Louis”), as well as other spots on school grounds, to get high at 4:20 p.m.

It has been said that this pack of teens would sometimes roam the campus in search of a rumored marijuana patch. According to a History.com report, the Waldos learned of a Coast Guard member who planted a cannabis plant and could no longer tend to the crop. In possession of a treasure map (some say provided by the plant’s owner himself) supposedly leading to the abandoned product, the group would meet at the Louis Pasteur statute regularly to conduct a search. The meeting time was purportedly 4:20 p.m, after practice because they were all athletes. The Waldos would pile into a car, smoke some pot and scour the nearby Point Reyes Forest for the elusive free herb. One of the original members of the Waldos, Steve Capper, told the Huffington Post: “We would remind each other in the hallways we were supposed to meet up at 4:20. It originally started out 4:20-Louis, and we eventually dropped the Louis.”

But credit for the spread and popularity of “420” indeed belongs to the Grateful Dead. Members of the Waldos had many connections to the band. According to Capper, “there was a place called Winterland, and we’d always be backstage running around or on stage and, of course, we’re using those phrases. When somebody passes a joint or something, ‘Hey, 420.’ So it started spreading through that community.” And the rest was history.

So there you have it. Happy 420 to the industry and please enjoy responsibly.