Every April 20, cannabis lovers have converged on the grassy knolls of Hippie Hill in Golden Gate Park to smoke marijuana and celebrate the “stoner’s holiday.”

This year, San Francisco took matters into its own hands and decided that with the recent passing of Proposition 64, which made recreational marijuana consumption legal in the state of California, it would permit the mass gathering of pot smokers, allowing for better waste management, fencing around the event and a larger police presence to keep the celebration under control.

This video takes a look at what it takes to put on a new, city-permitted 420 event of this magnitude.