It's a cloud of weed smoke so thick you can see it from thousands of feet in the air, hanging above Hippie Hill in Golden Gate Park's Robin Williams Meadow, right around 4:20 p.m. every April 20.
4/20 has long been an unofficial holiday to celebrate the enjoyment of cannabis in San Francisco, but now that weed is legal across California, the event has become a much bigger affair. As many as 20,000 people were expected for 2023's free celebration, with over 100 security guards and dozens of vendors — selling both food and weed.
"I think this is the one holiday San Francisco celebrates more than any other holiday," said a young woman wearing large flower-shaped earrings as she lounged on the hillside.
Of the thousands in attendance, many we spoke to said they were there for the first time.
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"It is so much fun, this is my first time being here," said a woman who told us she dyed her hair green just for the occasion.
Cannabis-themed outfits and anything green were the fashion trend of the day — even if it meant improvising.
"I'm not an A's fan," said a man wearing an Oakland Athletics jacket just hours after learning that the team had struck a deal for a ballpark site in Las Vegas. "Just green, just (wearing) green."
Though lines were long for the cannabis dispensary booths selling pre-rolled joints and edibles on site, lines were even longer for the vendors selling piping hot food.
"I'm just gonna smoke weed and eat some fries," said a man about to get in the rapidly-growing line.
"Garlic fries!" exclaimed one man who finally made it to the front of the line. "I think they're amazing, and I haven't even tried them yet!"
Nearby, another man had just finished dressing two hot dogs with a mountain of condiments and was preparing to chow down on them.
"We got ketchup, relish, sauerkraut, a little mustard on top just for the finish," he explained.
As 4:20 p.m. drew near, the crowd began making plans for the big moment — rolling joints and figuring out who to share them with.
"I've got the biggest joint here," proclaimed a man who said he's a five-time joint rolling world champion.
He held up a giant joint shaped like a cannabis leaf that he said contained half a pound of weed — a quantity worth hundreds or even thousands of dollars. He designed the joint to be passed around and smoked through the leaf's stem.
"The whole crowd's gonna hit this thing," he said. "We're gonna spark it right at 4:20."
With help from the emcee onstage, the crowd counted down from 10 as a gray haze rose up over the park. Then, it was time to go back to doing what they came there for:
"Just relaxing, smoking, having a good time," said a man hanging out with the green-haired woman we spoke to earlier.
Nearby, another man taking a deep hit off a vape pen proclaimed, "God bless America."
