Thousands expected to light up for 4/20 in San Francisco

SAN FRANCISCO (KGO) -- Thousands of people are expected to light up in Golden Gate Park for 4/20 today. San Francisco has the world's oldest and largest celebration of cannabis, and this year's may be even bigger.

At 4:20 p.m., thousands will converge on Golden Gate Park to light up.

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Last year, 15,000 people descended on Hippie Hill, which is now known as Robin Williams Meadow.

This year's event will be the first time recreational pot use is legal in California.

Officials say they neither condone nor sanction the pot holiday, but know it's not going away.

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"Love it or hate it, the historic 4/20 festival is not going away," said Supervisor London Breed.

Authorities say they're working with a private sponsor to pay for fencing, security and park maintenance.

VIDEO: San Francisco's 2017 4/20 celebration runs smoothly with no arrests

Dozens of city park and rec workers began the massive garbage pickup in Golden Gate Park following the popular 4/20 celebration Thursday.

Merchants partnered with the city last year to help with vendors, security and cleanup.

The partnership will continue this year with merchants raising $200,000 dollars for more porta potties, trash cans and security.

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