Nestled into the East Bay, the store is in Brentwood off of Heidorn Ranch Road.
"I mean it's a really big deal for us, the economic boost and the jobs, we were just talking to people who said 400 jobs, local jobs, that's fantastic!" Brentwood Mayor Susannah Meyer said.
With some rare, limited items available for the grand opening, it brought out people from across Northern California.
Some, started lining up as early as 10 a.m. on Thursday.
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"Camping out getting to meet new people and just talk about the different bourbons and where everybody is from," Justin M., an Oakland resident said.
He says he came specifically for the whiskey.
"All kinds of bourbons, all kinds," he said. "I'm happy with this one right here, Blantons."
While most shoppers had their eye on something, equally in demand.
"I was just hoping to get a carton of eggs, that's what I was hoping to get," Jesse Dela Cruz, an Oakley resident said.
Outside of the whiskey and eggs, Hokas, Birkenstocks and Crocs seemed to be some of the first items to go.
Mayor Meyer says this long-awaited grand opening has been in the works for years.
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The city even extended Sand Creek Road from Highway 4, just to help with the expected traffic congestion for the store.
Meyer says the city is hoping this store will bring in a minimum of $1 million in tax revenue a year.
"People always, they don't necessarily understand that these kinds of revenues are going to help with the streets, and all the maintenance of all the parks and those sorts of things so it does, it really means something to us, it's going to help us be able to keep that quality of life that everyone wants to move here for," she said.
And the Brentwood Chamber of Commerce says they're hopeful, this will lead to even more growth across the city.
"Not only is it good for our economy, for our jobs and our residents but also for potential growth and attracting other businesses like Costco," Adam Martinez, the Brentwood Chamber of Commerce President said. "So you gotta come to Brentwood and check it out."
The hype around this store is prompting traffic warnings.
The Antioch Police Department is advising drivers in the area to expect traffic delays and plan extra travel time.
Costco shoppers are advised to take the newly extended Sand Creek Road exit rather than Lone Tree Way.