The term "4/20" originated in 1971 when a group of California high school students, known as "The Waldos," used 4:20 p.m. as their designated meeting time to search for an abandoned marijuana crop.
- The Waldos: Five students from San Rafael High School coined the term as a secret code to meet at a campus statue and smoke weed.
- Grateful Dead Connection: The slang spread globally after the students shared it with members and roadies of the Grateful Dead rock band.
- Debunked Myths: Popular rumors claiming 420 is a police radio code or a California penal code for marijuana are entirely false.
- Cultural Milestone: The Oxford English Dictionary officially credits The Waldos for the term, which has evolved into a global cannabis holiday and commercial phenomenon.
Five former students from San Rafael High School in Northern California have been officially credited with creating "4/20," the universal code for marijuana culture. What began in 1971 as a secret meeting time for a teenage clique has transformed into an international cannabis holiday, influencing everything from legalization activism to mainstream commercial branding.
The creators, a group of friends who dubbed themselves "The Waldos" because they hung out by a specific wall, coined the term out of necessity. In the fall of 1971, the teenagers acquired a hand-drawn map allegedly leading to an abandoned marijuana garden at the nearby Point Reyes National Seashore.
Because school and sports practices ended late in the afternoon, the group agreed to meet at exactly 4:20 p.m. in front of the school's Louis Pasteur statue to begin their treasure hunt.
The group would pass each other in the hallways, whispering "420 Louis" to confirm their after-school plans. While they never actually found the legendary marijuana crop, the shortened code "420" stuck as their private slang for smoking weed, helping them hide their activities from parents and authorities.
The term's global explosion is largely attributed to the Grateful Dead. The Waldos had personal connections to the band—one member's brother was close friends with bassist Phil Lesh. As the teenagers hung out backstage, the slang was adopted by roadies and fans, known as Deadheads.
In 1990, an editor for High Times magazine saw the term explained on a Grateful Dead concert flyer, prompting the publication to adopt and popularize the code worldwide.
Despite the documented history—now officially recognized by the Oxford English Dictionary—several persistent myths surround the origins of 4/20. Common misconceptions include:
- California Penal Code: Rumors suggest 420 is the penal code for marijuana use. In reality, Section 420 refers to obstructing entry on public land.
- Police Radio Codes: It is widely and falsely claimed to be a police dispatch code for "marijuana smoking in progress."
- Chemical Compounds: Some believe marijuana contains 420 chemical compounds, but the actual number is 315.
- Celebrity Deaths: The date April 20 is incorrectly linked to the deaths of icons like Jimi Hendrix, Janis Joplin, or Jim Morrison, none of whom died on that day.
Today, April 20 serves as a global day of celebration and activism. The number has become so ingrained in the culture that California's 2003 landmark medical marijuana legislation was aptly named Senate Bill 420.
After decades of watching businesses capitalize on their teenage inside joke—from "420-friendly" hotels to branded merchandise—The Waldos are finally participating in the industry. The group has recently partnered with cannabis and beverage companies, cementing their legacy in the culture they inadvertently created.

