The Hideout is officially old enough to drink. The venerated bar and music venue celebrated its 21st anniversary this weekend by bringing back its beloved block party—this time, a two-day affair—with a long lineup of bands including Eleventh Dream Day, Condo Fucks (aka Yo La Tengo), and Screaming Females.

Last month, co-owner Tim Tuten told Chicago that this year's party could be the last of its kind, as the surrounding area braces for redevelopment. "The neighborhood is changing, and it's the end of things as we've come to know them," he said.

With that in mind, we spoke with long-time patrons and employees about what makes the Hideout Block Party unique, and about their favorite memories of the party that's hosted musical legends like Mavis Staples and Wilco.

Tim Tuten, co-owner: We bought the Hideout in October 1996, so the first year, ‘97, the block party was just a party, a barbecue. We did a big show outside, and we were hoping 100 people would come.

Mark Stanley, patron: In one of the first years, they had a little tent with a circus performance in there, including a guy walking on a rope. I remember standing there at the side of the tent, and I said to my wife, “That's Jeff Tweedy over there.” And then all of a sudden Wilco's playing, and there were like 100 people there. I was like, “Damn, this is as good as it gets.”

Tuten: We just kept doing it every year, and each year it just got bigger and bigger and bigger, until we were in the parking lot, until it just grew into 7,000, 8,000 people, and we had big bands. The whole key was that every band that played at the block party was a band that had played at the Hideout, and then they became too successful for the Hideout, which is awesome.

Stanley: The bigger festivals were a lot of fun. But it was like a boil. It started small, and just got bigger and bigger and bigger, and then I think it just overcame Tim and Katie [Tuten] and their partners, and they had to take a step back.

Sheila Sachs, volunteer and merch designer: The best memory was when Neko Case had a birthday, and co-owner Katie Tuten sent our friend Howard to make sure I was backstage for the birthday cake. So I come running downstairs, get in the golf cart, and Howard starts driving through the crowd with me and his kids on the back. Then he decides he can't get through, so he just reverses it. Now one of his kids and I are in the front, going backwards through the crowd, and we're like, "Move! Move! Everybody move!” so that we could race backstage to sing “Happy Birthday.” I abandoned my post to sing “Happy Birthday” to Neko.

Mark Greenberg, Musician (Eleventh Dream Day): There's a great story from the year that had Mavis Staples. They gave a rider of their needs on stage. The rider said, “In the drums, we need a drum set, a 20-inch bass drum, and a throne.” In musical circles, a throne is a drum throne, it's a seat. Here, they made from scratch this beautiful, ornate throne with Mavis's name on it. If you go inside the Hideout, you’ll see it upstairs. It's just plush and unbelievable. Of course, when the band showed up, she's like, “What's this?” And they're like, “This is the throne.” So of course she sat in it, because it definitely took like 40 hours to make this amazing throne. That's a real good example of the Hideout, just going way over the top to do something.

Jon Langford, musician: One year, we brought the Welsh Male Voice Choir down from Toronto. We had just came off the stage, and I was standing backstage with my kid at the time, he was about 8 years old. A limo pulls up and Mavis Staples got out. I’m standing with 30 or 40 drunk Welsh guys who've just been singing on stage, and Mavis Staples walks up to us. I say to my son, “She's one of the greatest singers ever in the world.” So he ran up to her and gave her a big hug. It was this great moment.

Tuten: What was memorable was Glen Hansard. His band the Frames just weren't big in the U.S. then, and he would play at the Hideout. Once they started getting a little bigger, they got booked at Metro, and the night before, he said, “Can I come try out some new material?” So he came to the Hideout and tried out [songs from] The Swell Season, the music for the movie Once, which came out a couple of months later. We just thought it'd be a little cool project, but then it won a Sundance Award, and he got nominated for an Oscar. In the meantime, we asked him to play the block party and he said, "Hell yeah." Between November and March, he won the Oscar. He blew up, and did our block party with Iron and Wine. We literally saw this guy with like 40 people in the back room of the Hideout, and one year later he drew 8,000 people.

Jefferey Allen Thomas, musician and former employee: I worked at the Hideout for 14 years, and I met my wife here. Ten years ago, I noticed that she was making eyes at me in the bar. Now when I was a bartender here, I kind of had a rule not to date anybody when I was working because it's cliche. I had a rule, but she was really pretty. I said, “If you want to hang out with me, I’m performing at the Hideout Block Party this year.” She showed up right before I was about to perform with a band called Mucca Pazza. That night, we stayed here, sitting on this deck, until about 3 in the morning, just hanging out and talking. She drove me home, and I said, “Are you gonna come tomorrow?” And she said yeah, and we hung out the entire day until late at night. She took me home again and I asked her to come back Sunday. We hung out that entire night, and I never had a night alone after that. We're married and have two kids.

Julia Adams, former co-owner of Lounge Ax: I remember there was a big anniversary for the label Touch and Go. It was in the parking lot next door. There were two stages, and it was like trying to run back and forth to see the bands that you wanted to see. I especially remember Arcwelder, one of my favorite acts that I never got to see at Lounge Ax. It was raining and it was early on Sunday, and I just remember standing there in my raincoat and baseball cap. There were maybe 100 diehard fans of Arcwelder there.

Langford: We got sponsorship here from Lagunitas, who basically gave us a lot of free beer. When it comes down to it, this isn't about trying to squeeze as much money out of people as possible. A lot of these festivals you see across the country now, they're corporations trying to be hip and trying to be cool. This genuinely is hip and cool.