Hop Jam is underway in the Brady Arts District.
The festival, founded by the Hanson Brothers, showcases music and craft beer.
Breweries are set up on Main and Cameron.
Oklahoma brewers say the event is helping their businesses.
Vendors and volunteers spent the morning Sunday gearing up for one of the largest craft beer festivals in Tulsa.
"This kind of exposure is wonderful,” John Elkins said. “You can't get this kind of exposure without something this big and something this crazy going on."
Elkins owns Elk Brewing Company, a fairly young brewery out of Oklahoma City.
They've been making Oklahoma brew since 2014, and this is their second time here in Tulsa for Hop Jam.
Elkins says it's a great way to get new people to try their beer.
“We get a lot of first timers trying it, which is kind of the goal,” he said. “That's the key. Get those first timers, get them in, let them try it and see what they think."
Half of the vendors on Main are local Oklahoma brewers -- big and small –with some names you'll recognize.