Thousands gather for 4/20 at San Francisco's Golden Gate Park

An estimated crowd of 15,000 people gathered at Golden Gate Park on Thursday for what was likely the biggest pot party celebration in the Bay Area.

The event isn't technically legal yet, but that wasn't stopping anyone from attending the International Pot Smoking Celebration known as 4/20.

The city and Haight Street merchants worked together to make this event safer and less of a nuisance.

The difference started at the security gate. There was one this year, where park rangers checked bags for weapons and glass bottles.

The city teamed up this time with local merchants to make it a safer event.

PHOTOS: Thousands gather for 4/20 celebration at Golden Gate Park


"What we are trying to do is provide the infrastructure to ensure that it happens safely for the people here, for the park and for the neighbors," SF Rec & Park Public Affairs Director Sarah Madland said.

While California's recreational marijuana legalization doesn't fully take effect until next year, the city decided it's better to help reign in the event rather than stop it.

Rec and Park spent about $50,000 on cops and park rangers on the perimeter. Local merchants spent $100,000 on security inside, as well as port-o-potties and trash cans.

"It's safer and cleaner, right? And I think that's a better step moving forward. I'd rather have it existing than not existing," Haight St. Merchants Association spokesperson Alex Aquino said.

RELATED: How April 20 became a pot day

The same goes for people who were rolling up, lighting up and loading up. A man, who would only call himself Sam I Am, was in the park for the Summer of Love in 1967.

"As soon as I came in the door, ran into a really nice couple and their son sitting there selling edibles. So I'm pacing myself," Sam I Am said.

One 4/20 participant likes this year's version better than last year's, which left 22,000 pounds of trash on the park grounds. "That's why there's security here this year. They were pretty out of control last year," Amanda Samson said.

It's estimated that there will be able 10,000 pounds of trash collected, around half of what was collected last year.

RELATED: SF announces new regulations for 4/20 in GG Park

ABC7 News was told pot smoking was OK, but no selling inside the event was allowed. Based on what we witnessed, that's not entirely true. But no arrests have been made.

"Everybody's smiling, everybody's having a good time, there's good music, weed, food, why not," 4/20 participant Marina said.

Officials say there were eight medical service calls Thursday with two of those people transported to the hospital.

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