Hideout (Chris Sweda/Chicago Tribune)

The Hideout was built on dirt.

It was constructed directly on top of the soil, a stone's throw from Goose Island, before the Kennedy expressway loomed at its right and Home Depot sprawled on its left, before it became a bar, then a bar and a place to see bands, then a bar and a place to see bands and a grab bag of book-release parties, hipster bingo nights and Saturday dance shindigs. The house at 1354 W. Wabansia — as ramshackle-looking as any 19th-century sea captain's shanty, as ordinary as any serial killer's domicile — has no foundation, no basement to speak of, just a cement frame at its edges and an aesthetic constitution a touch more durable.

"Whomever built it probably thought, 'Let's do this for cheap,'" said Tim Tuten, the bar's co-owner, institutional memory and extremely-difficult-to-shut-up public voice. "It was probably illegally built back then."

Tim Samuelson, the city's cultural historian, figures it most likely became a bar around 1919, about the time that Prohibition went into effect. "The rest of the history is pure working-class stuff," Tuten said. "It was likely built by Irish workers in the late 1800s, then over time went from being a home to a public house, then an illegal bar run by Irish bootleggers — the Irish were dredging the Chicago River then, and building the grain elevators around Goose Island, building the subways. So Prohibition ends in 1933. And then it becomes an legal bar in 1934 — also called the Hideout. Then it falls into the hands of the Italians, who ran it for 49 years.

"Then we come in."

By the mid-1990s, the Hideout was decaying, imploding — the ceiling sagging, the wooden floor buckling. "The regulars would say to me, 'You're going to turn this into a yuppie bar and kick us out' and I would spend countless hours explaining, 'No, see, I work for the city, you work for the city, I'm a public school teacher …' Some stayed. But some would just look at me and listen and say 'Bull----. You went to college.'"

This weekend, 15 years after Tuten, his wife and two of Tim's grade-school friends transformed it from an after-work dive bar into a dive bar with a serious (and ambitiously eclectic) aesthetic, the Hideout celebrates its anniversary with a big block party, an all-day concert featuring many of the bar's longtime friends (Andrew Bird, Mavis Staples) and young charges (White Mystery, Kids These Days); tonight, next door at High Concept Laboratories, there's a photo retrospective of the bar's long history. It's a moment for appreciation, for remembering where the Hideout has been. It's also a time to consider where Chicago's best open secret, "the neighborhood bar without a neighborhood," is headed — and for reminding yourself nothing lasts forever.

Last spring the city began fixing the sidewalk along Wabansia Avenue, the broken, uneven, pock-mocked excuse for cement that stretched from Elston Avenue to the City of Chicago's Department of Fleet Management, past the low slung chocolate brick building that houses High Concept Labs, past the faded red bricks of the building at the end of the block and past the Hideout's house, the sides of which seem to slump against its heftier neighbors, looking meek and awkward, like a hippy sandwiched between linebackers on a bus ride.

The city worked on Wabansia Street itself, too. This proved an inconvenience for the Hideout. The only way to get in was to step across a wooden plank, which ran from the street to the front door, carrying you over the spring mud and muck. And then, recently, it was over, the construction was finished. The space out front now resembles a typical Chicago neighborhood sidewalk, wide, pale and spotless, with large cement squares separated by patches of grass holding thin trees, white strings dangling around their young trunks.

It's all so wholesome and normal – all so Lincoln Park – the sprucing-up rattled Tim Tuten.

"We love the post-industrial order of this area, the whole grittiness of it," says Tuten. "But those sidewalks! And those nice trees! I do appreciate it. (Richard M.) Daley never came to the Hideout. He was invited many times. And I think that the last thing he did in office, just to irritate me, was to fix the sidewalk in front of the Hideout."

Mike Hinchsliff, who, with his identical twin brother, Jim, makes up the other half of the Hideout's ownership, laughs at Tim's paranoia. And then he turns serious – "I think residential encroachment is a ways off. But something is up. It looks too nice." Rob Miller, the founders of Bloodshot Records, which uses the Hideout like an unofficial headquarters, agrees, "'Development' was my first thought. It's Chicago, who knows what's going on behind the scenes? Someone sees this area and has a billion dollars in his eyes."

Mind you, a sidewalk was fixed.

Not much else.

And yet slight anxiety over such a modest change to its environment speaks volumes about the Hideout — how it's remained a freaky anomaly on the Chicago bar scene, why any drift toward the mainstream raises its hairs. See, for a century, the Hideout, in one permeation or another, has willfully avoided the rest of the city, its gentrification, the forces that demand a watering hole evolve, change its habits — early on, despite the Hinchsliff's suggestion, Katie Tuten, Tim's wife, even refused to install more than one television on the grounds that the tempting flicker would alienate customers from each other, smothering the cultivated vibe.

It's also, geographically speaking, lucky, ideally suited for isolation. The Kennedy helped it weather the Wicker Park and Bucktown hipster boom of the '90s; the north branch of the Chicago River and North Avenue Bridge, shielded it from the double-wide stroller crowd to the east. (The staff argues over whether the bar is located in Lincoln Park West or Bucktown East; though actually, technically, it's in Bucktown.)

And then there's the place itself, too personal and random and intimate to fit anyone's idea of self-conscious or insufferably hip — Chicago singer Kelly Hogan, who was a bartender at the Hideout for 10 years, says the Hideout looks like it was decorated by Girl Scouts. Which is spot on. If you've never been there — "and it's amazing how many people have lived here their whole lives and never heard of this place," said employee Ryan Hembrey — a brief tour: The front room is small and boasts a shrine to the late singer Selena, an old cash register with rounded typewriter keys and a $4 dollar cocktail named the Wooden Leg; the back room, where bands play, is decorated with gold tinsel, chipped plastic swordfish, white lights and a stage Tuten and Co. built themselves, though it appears better suited for elementary school Christmas pageants.

Capacity is 150 people.

It rarely feels overcrowded, yet feelings for the place are so warm, it's been the home of weddings, bar mitzvahs and funerals. Also, an occasional game show, potluck dinner, play, movie, benefit, tribute concert, metal show and comedy night, as well as the monthly Interview Show, which is exactly what it sounds like. The Swell Season, the two-piece Irish group that starred in the Oscar-winning "Once," developed material here (and years later, threw a party here after playing a sold-out show at the Chicago Theatre). The New Pornographers used the bar as an early launching pad — one of the Hideout's sometime bartenders, Neko Case, later joined the band. The White Stripes, Iron and Wine, St. Vincent - all played surprise shows here. Wilco tested out new songs here. The other night, Dan Sinker, the Columbia College professor who was the profane tweeter behind @MayorEmanuel, had a book-release party here, visited by the real Mayor Emanuel and Jeff Tweedy of Wilco, who performed a solo acoustic version of "My Humps" by the Black Eyed Peas.