What began humbly in 2001 as the "Strictly Bluegrass" festival (if you didn't have a banjo or a mandolin, you probably weren't welcome) attached the word "Hardly" in 2004, reaching out to include acts from other genres and traditions. And suddenly in the last few years, it has transformed into one of the most celebrated music festivals in the country.
It's also ballooned in size: Ten years ago there were two stages and 20,000 people in attendance at San Francisco's Golden Gate Park. This year there were six stages, and an estimated 800,000 turned out over the three-day event to see legendary acts like Robert Plant, John Prine, Gillian Welch, Kris Kristofferson and Merle Haggard, as well as current indie-folk mainstays like Bright Eyes, M. Ward and the Felice Brothers.
The welcoming spirit of the festival hasn't changed. Musicians, like the audiences, quite openly enjoy themselves -- just happy to be a part of this enormous weekend -- and often they combined forces. Patty Griffin stepped in to sing with her boyfriend Plant, and Steve Earle and Welch joined Emmylou Harris for her encore. Part-time musician and "House" star Hugh Laurie played a set of New Orleans blues before, as SF Gate reported, he hopped onto a golf cart to catch Haggard and Kristofferson's set.
"It's not just hippies here," said Brian Arn, a 62-year-old lawyer from Sacramento, who came with his wife, Ellen, a homemaker. "That's the thing: it's babies. It's old farts. It's families. Everyone."
Behind each stage hung a banner devoid of any corporate sponsorships or brand alliances -- the only image was a headshot of Hazel Dickens, a legendary bluegrass performer who passed away last year and to whom this year's festival was dedicated.
"A free festival with no corporate sponsors? How about that," said Kevin Drew of Canadian indie rock act Broken Social Scene, before they launched into their set.
And that might be the most remarkable thing about the proceedings last weekend. Since 2001, the festival's bill has been footed entirely by one bluegrass fan, musician and investment banking billionaire, Warren Hellman. Indeed, this 77-year-old covers sound equipment, security, park rental, everything -- himself.
So how much does something like this run?
"What I can do is allow you to do the arithmetic without telling you," he told SF Weekly last year. "There are 80 bands. Let's assume that they average $2,500. And let's assume that the overhead is 50 percent more than that. I didn't tell you what it was, but you can get certainly within a few gazillion dollars of the amount."
This one-man sponsorship machine explains the occasionally muddied sound and pedestrian traffic, but also the gratitude that everyone feels for him and for the gift he's providing the city. Every year, stacks of personal thank-you cards turn up at the offices of Hellman & Friedman, his private equity investment offices.
Moments before he spoke with The Huffington Post, he was onstage to watch Gillian Welch's afternoon show from the wings, and hours earlier he had sat in on Earl Scruggs' set, playing his banjo.
"I'm stunned at this turnout," he said, looking out at the crowd from behind the festival's main stage.
His own band, The Wronglers, had played earlier that Saturday morning under an overcast sky. Hellman wore a spectacular black jacket, sparkling Stars of David along the sleeves, designed by his granddaughter.
"The first year we did this, we had Emmylou [Harris] and Hazel [Dickens], and I remember asking if maybe three or four thousand would show up," Hellman said. "And there were 20,000 that year. I just had no idea what the reaction would be to this kind of music. Our band was used to playing a Chinese retirement center with 10 people in the audience."
Perhaps it's the resurgence of a more earnest, back-to-basics mentality that inspires so many people brave heat, crowds and some of the foulest porta-potties in America to watch Gillian Welch croon "I'll Fly Away" or John Prine suggest you "Blow up your TV / throw away your paper / Go to the country, build you a home." Both acts had three or fewer musicians onstage, but managed to hold the massive, all-ages crowds in a rapturous hush.
Or perhaps it's because the concert is free. Or because the police turn the other way when a 70-year-old contractor lights up a joint ("I should warn you, smoking marijuana can lead to tobacco," Robyn Hitchcock joked). Or because when a father and his daughter pass by you on the left to get closer to the stage, they warn, "My apologies, but we're coming up on your left-hand side now," instead of merely shoving you to the right.
"Everyone in this entire city since I got here has been in just the best mood," said Welch. "I've gotta think this has something to do with it. What a magical place."
Golden Gate Park has a storied history of free music festivals, beginning with the "Human Be-In" of 1967 -- a lot of Grateful Dead and LSD then -- and continuing through to the Chet Helms memorial in 2005, which brought a Jefferson Airplane reunion along with it. Hardly Strictly Bluegrass continues in that vein and will hopefully last long after Hellman has passed (even though, he suggests, some younger members of his family aren't too keen on that.)
The only discord of the weekend came when San Francisco's mayor, Ed Lee, took to the mainstage to scattered boos to thank everyone for coming out. The mayor then presented Hellman with a plaque of appreciation.
"This is one of those special things our city does," Mayor Lee told HuffPost. "For me, it's like the World Series. I mean, you have 800,000 people in one place! I love how diverse it is; it's an easy atmosphere, and you don't feel insecure. That's a special thing."
On Saturday night, the second full day of music closed with a set from Texas country legend Robert Earl Keen. A few of the long-haired types cleared back to make room for some cowboy hats and tucked-in polo shirts. A few alumni from Texas A&M next to me -- they worked for Chevron -- knew all the words to his songs.
"Keep dancing," Keen suggested.
And everyone -- babies, old farts and a few lone teenagers on the hill behind the stage -- obliged.
Check out some user-submitted photos of the event below: