The number 420 has had special meaning in the cannabis community for decades. During the long period of prohibition, “420 friendly” was a way to signal affinity, and 4/20 was a day to light up in protest of restrictive laws. For some, 420 was a reference to getting high, and for many more, 4:20 pm has become the weed version of cocktail time.

There are a lot of myths about the origin of 420—that it was an old-time police code for a pot bust, that it signifies the number of active compounds in marijuana, that 4:20 is tea-time in weed-friendly Amsterdam—but they’re all wrong.

Seems the true origin of 420 goes back to an unlikely group—five stoner jocks in San Rafael, CA who called themselves the Waldos. Way back in 1971, the Waldos met after sports practice each day at 4:20 pm, and then set off on repeated (but never fruitful) searches for an abandoned marijuana garden near Point Reyes. Of course, they toked up to make the search more fun, and while they eventually gave up their quest, referring to 4:20 as their time to get high stuck with them. Through later connections between the Waldos and the Grateful Dead, the use of 4:20 spread from them to the crew to the band to the Deadhead community, and the rest is history.

If you want to learn more about the true 420 origin story, hear some other almost-believable origin myths, or ponder some interesting facts about the date 4/20, the time 4:20 and the number 420, read on.

The Real 420 Origin Story

According to the Huffington Post (and several other reputable sources we checked), the origin of 420 goes back almost 50 years ago, to a group of teen athletes in San Rafael, CA, who’d heard about a marijuana garden abandoned up the coast near the Point Reyes Coast Guard Station. The group called themselves the “Waldos” after a wall outside their school where they met each day after practice, at 4:20pm.

“We would remind each other in the hallways we were supposed to meet up at 4:20.” Waldo Steve told the Huffington Post. “We’d meet at 4:20 and get in my old ’66 Chevy Impala and, of course, we’d smoke instantly, and smoke all the way to Pt. Reyes and smoke the entire time we were out there. We did it week after week,” says Steve. “We never actually found the patch.”

So how did it spread from teenagers in San Rafael to the rest of the world?  Based on the Huffington Post’s research, it was a serendipitous connection between the Waldos and the Grateful Dead. “The Dead, according to Waldo Dave Reddix, ‘had this rehearsal hall on Front Street, San Rafael…we used to go hang out and listen to them and get high.’ The Waldos also had access to Dead parties and rehearsals. ‘We’d go with {Mark’s} dad who was a hip dad from the ‘60’s,’ says Steve…’ When someone passes a joint or something, ‘Hey 420.’ So it started spreading through the community.’”

The Huffington Post recounts how one thing led to another and the term started to catch on. “As the Grateful Dead toured the globe through the ‘78’s and ‘80’s, playing hundreds of shows a year, the term spread through the Dead underground. Once High Times got hip to it, the magazine helped take it global.” High Times editor Steve Hager is convinced the Waldos are the source. “No one’s been able to come up with any use of 420 that predates that 1971 usage, which they had established.’” Hager told the Huffington Post. “’So unless somebody can come up with something that predates them, then I don’t think anybody’s going to get credit for it other than them.’ He says.”

Until the real origin of 420 was brought to light, a lot of myths were circulated about it—some quite believable, others pretty out-there.

Myths about 420: True and False

  • Bob Marley died on 4/20. False
  • Hitler’s birthday was 4/20. True
  • The universal police code for a cannabis bust is 420. False
  • The clocks in “Pulp Fiction” were all set at 4:20. Almost True (a few hard-to-read clocks weren’t)
  • The Columbine Shooting occurred on 4/20. Sadly true
  • 4:20 is tea-time in the Netherlands. False—there is no accepted tea-time in the Netherlands
  • 4:20 is when the first dose of LSD was taken. True—by a Swiss Chemist in 1943
  • There are 420 active chemicals in cannabis. False—there are more than 500!
  • The California House Bill, legalizing medical marijuana, was #420. Deliberately true
  • 420 comes from a Who cover; a Bob Dylan Song; a Crosby Stills and Nash Song. False, false, false.
  • Jerry Garcia died at 4:20. Close, but not quite—he died at 4:23
  • The numeric value of the letters in Home Grow Community LLC equal 420. We’re not saying—you’ll have to do the math yourself…

Fun Facts about 420

  • It would take a typical person about three minutes to count from 1 to 420.
  • The world’s largest 4/20 event, The Mile High 420 Festival, is held each year at the Denver Civic Center.
  • Using 25 years of U.S. national data, one study found a 12% increase in the risk of fatal motor vehicle crashes between 4:20 p.m. and midnight on April 20.
  • Following the success of Washington, D.C.’s initiative 71 to legalize cannabis, Mayor Muriel Bowser granted license plate number 420 to the campaign’s leader, Adam Eidinger.
  • 420 mile markers have been stolen so many times in Colorado, the state has replaced them with 419.9.
  • What do Carmen Electra, Luther Vandross, Jessica Lange, and Steve Marley have in common? They were all born on 4/20.
  • 420 squared is 176,400; the square root of 420 is 20.4939015319.
  • 420 is an even composite number composed of four prime numbers multiplied together.
  • What do these completely unrelated events have in common: the official opening of Fenway Park in 1912; the Soviet army began shelling Berlin in 1945; Barbara Streisand recorded “We’ve Only Just Begun” in 1971; Michael Jordan set an NBA record with 63 points in one game in 1986; Chicago Bulls won a record 72 games in a season in 1996; Deepwater Horizon oil rig exploded in 2010. They all happened on 4/20, of course…

Read More for Yourself

Myth Sources

Prohbtd

Leafly

Wikileaf

Huffington Post

Wikipedia

Fun Fact Sources   

Wikipedia

Grass City

On This Day

Numbermatics

For a list of 4/20 events in Massachusetts, check out this comprehensive list of 420 events.