Why Is It Called 4/20 Anyway?

Happy 4/20, hippies! In honor of marijuana's biggest day of the year, potheads nationwide will light up $4.20 joints, throw 4/20 concerts, hold 4/20 bake-offs, ring in 4:20pm—and some will even do it legally, now that the Man has horned in on the action—all in celebration of their favorite, well, herb. "Most of our chapters are in celebration mode," says pot legalization advocate Allen St. Pierre. "That was not the case 10 years ago; 4/20 was a day of protest." But why 4/20? The number of chemicals in pot? The obscure multipliers in that Bob Dylan song? The Fresno Bee checks in with Steven Hager, the former editor of High Times, who says he first saw it referenced at a Grateful Dead show in 1990: A flier being passed around invited potheads to show up at 4:20pm on April 20 for a little "420"-ing. Intrigued, Hager dug a little deeper and found "it's not any of these other crazy coincidences that people bring up."

The term dated back another two decades to a group of five San Rafael High School students dubbed the Waldos. In 1971, they were given a "treasure map" to a weed patch, and agreed to meet after school at 4:20pm. They got high—which eventually turned into a daily after-school activity—and went out searching. "I thought, 'This is important!' And you know everybody thought I had lost my mind," says Hager. "I started talking to people and I said we will build everything around 420—420 is the new everything." And it worked: Hager's pet project is now a marketing juggernaut. "Without him, I don't think there's any way that this interesting numerology that has crept deep into American culture and commerce would have happened," says St. Pierre. (Hey, Roseanne Barr is a fan.)