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OAKLAND, Calif. - The legendary 4/20 celebration is returning to San Francisco's Golden Gate Park's Hippie Hill on Thursday.
An estimated 20,000 people will gather for the annual cannabis festival at Hippie Hill, officially known as Robin Williams Meadow.
A plume of marijuana smoke can usually be seen above the park when the clock strikes 4:20 p.m.
City officials say they are ready. Entry to the cordoned-off area in the park is free and begins at 10 a.m. The party starts at noon.
In addition to cannabis and food sales, there will be live DJs, guided meditation, Aztec dancers and yoga sessions. R&B singer Erykah Badu is scheduled to perform.
Cannabis products will be sold at the event for the second year in a row. Because of this, nobody under 21 will be allowed to enter the fenced celebration area, officials said.
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"The 420 festival is about joy and positivity. Thank you to the event organizers, City staff, residents, merchants and the community who work hard to ensure it’s fun and safe for everyone." said District 5 Supervisor Dean Preston. "I want to encourage everyone to take public transit, enjoy the camaraderie and music, and have a great time."
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Security will be at the park entrances and will check the identification and bags of those coming to the festival, officials said.
Event organizer Alex Aquino with Sounds Bazaar said this celebration started out underground but has become a cultural event. "It's always been a community, cultural event," said Aquino. "But, it was just unsanctioned, so now we have the infrastructure that's been seven years building, right?"
Mayor London Breed touched on how the event has evolved.
"The 420 celebration of today is much different than the 420 celebration of years ago thanks to the hard work of our City and community partners organizing the event," said Mayor Breed. "I am asking everyone to do their part by respecting our parks and neighbors while having a good time. I am grateful to the event organizers and the work of all of our City departments for making sure this event runs smoothly."
Cannabis enthusiasts said they're planning on showing up and toking up on a substance they say should never have been criminalized. "Among all the substances that there are, this one has the cost-benefit analysis that's the best for most people, you can be in great shape," said Fred, a cannabis smoker from Oakland, who did not give a last name. "I mean, I'm in fantastic shape and I smoke weed all the time, you can lead a normal life. It doesn't beat the hell out of you like so many other things."
Agencies are working together to lessen the neighborhood impacts of the massive party. Officials said there will be 100 security guards, 25 park rangers, 163 portable toilets, free Muni shuttles, and multiple parking officers and clean-up crews.
The city is asking those attending to be good visitors.
"Respect our parks, respect our surrounding neighborhoods, respect each other," said Tamara Barak Aparton from San Francisco's Recreation and Parks Department. "We want everyone to have a great time. Throw away your trash, pick up after yourself, leave things as you found it."
Significant congestion in the area is expected from 3 to 7 p.m., and officials ask drivers to avoid the area during that time frame.
No road closures are currently planned outside of Golden Gate Park. However, onsite traffic management teams may close streets as needed for public safety, officials said. Additionally, Muni routes 7, 33, 37, 43, and 66 lines may be rerouted if streets are closed.
"This year’s 420 will be a great mix of performances, health and wellness activities, cannabis brands, and community organizations," said Aquino. "We are a community and cultural event based on sponsorship and donations, and we are so grateful for everyone’s support."
KTVU's Christian Kafton contributed to this story.