The gates opened at 11 a.m. to the public on Friday.
VIDEO: 7 ways to rock Outside Lands like a pro
Michael Tosini is about to make a lot of friends. "People get very thirsty here," he said. He's running one of the many beer booths at the festival. "I don't really know the numbers, but they're pretty high. I would say more than a keg a person, but that's probably a lie," he said.
Other bartenders aren't quite sure what to expect. "It's my first Outside Lands, I'm really excited," Ali Manuel said. "If you're having a good time, everyone else will have a good time."
The festival offers wine from 40 northern California wineries and beer from 30 west coast breweries.
About 80 local restaurants will cater to the crowds as well, including Big Chef Tom's Belly Burgers. This is his fifth Outside Lands. His booth is just off the main stage. "It's really loud, so you're yelling back here, essentially. I like the calm back here, it's misty, perfect Golden Gate weather, before the storm so to say," he said.
VIDEO: How to find your way around Outside Lands
The festival gives the city a huge economic boost, generating about $60 million this weekend.
Just a word of warning, it's quite misty and cool in the park Friday, so dress accordingly.
For a full list of road closures in San Francisco this weekend, click here.
Click here for more information and click here for the full lineup.