“15 years, we’re having a party.” That was Disney World’s anniversary slogan when my parents took me to Orlando, Fla., in 1986 and the jingle immediately warped my impressionable, five-year-old brain. The fact that an amusement park had grown into its own living organism over the previous 15 years—simultaneously changing and staying the same while welcoming new generations of fans year after year—seemed like the ultimate marker for what I’d later learn to call the passage of time.

And here we are 30 years later—a day into Bonnaroo’s own 15-year party—and I find it equally hard to wrap my head around the fact that this “magic kingdom” has already existed for a decade and a half. It’s been a heady journey watching and tracking the festival’s evolution since the inaugural edition in 2002—first as a fan camping in a field named after a cartoon character and later as an entrenched editor of this here festival rag. When Bonnaroo dropped its initial artist announcement through a handful of archaic proto-social media/pre-smartphone digital platforms, it felt like the burgeoning jam scene’s pinnacle. Over the years, Bonnaroo has gradually progressed from that narrow, but good-natured idea to the U.S. version of Glastonbury and its own generational rite of passage. It’s a place where all types of music fans can come together and camp out on winemaker Sam McAllister’s old farm for a Woodstock-esque weekend. Like anyone lucky enough to return to Great Stage Park year after year, I’ve seen my own musical tastes evolve—along with my waist and hairline—during that time, too. Yet once the Tennessee sun sets over the cosmic Centeroo Ferris wheel, the years feel more like footnotes than eras.

It’s strange being nostalgic for a festival based on the Summer of Love ideals of improvisation and living in the moment, but it also feels right for an event rooted in the Southeast’s own traditions and native dialects to honor its legacy. A few familiar faces from the very first Roo will also perform this weekend—including Bob Weir, Les Claypool, Ween, Eric Krasno and DJ Logic—and many other names on this year’s marquee, like Macklemore & Ryan Lewis, Chris Stapleton, Death Cab for Cutie, Band of Horses, Grace Potter, Jason Isbell and Ed Helms, have long since became tried-and-true Bonnaroovians.

Which is why Thursday night has always been my favorite part of this long, lost weekend. There’s a familiar mix of back-to-camp excitement as fans and musicians alike settle in and reconnect. (The refurbished disco-ball tower imagined by Radiohead lighting and stage designer Andi Watson and permanent bathrooms—let’s face it, this year’s true headliner—are new this June. Hamaggedon and The Farm’s signature fountain remain reliable standbys.)

Thursday is also a day of discovery, a chance for emerging acts across a kaleidoscope of sounds to win new fans without competition from the stadium-sized Which and What Stages. Ever since Bonnaroo started hosting music on Thursday night in 2003—the festival was only three days in 2002 and Bonnaroo’s promoters pulled a Beyoncé the next two years—the evening has served as a debutante ball for “voices of their generation” like Zac Brown Band, Vampire Weekend, Ray LaMontagne, Kendrick Lamar, Alabama Shakes, Father John Misty, MGMT, Childish Gambino, Passion Pit, Jack Antonoff, Portugal. The Man, Janelle Monáe, Blitzen Trapper, Miike Snow, Best Coast, Alt-J, HAIM, Courtney Barnett and White Denim.

Last night’s festivities, by and large, stayed true to Bonnaroo’s dual themes of ritual and rite of passage. Alt-pop electronic act Lanny and R&B personality Roman GianArthur, both of whom have earned blog accolades in recent months, officially kicked off Bonnaroo’s big-stage festivities in This Tent and The Other Tent, respectively; GianArthur took an early lead in the “musical tribute department” by bookending his high-energy show with faithful covers of Prince’s “Let’s Go Crazy” and “Purple Rain.” Soon after, San Francisco funk act Con Brio officially christened That Tent, kicking off a stretch of acts that included New York blues-rockers The London Souls and Australian electronic duo Hermitude. A welcome nod to Bonnaroo’s original hippie ethos, That Tent also hosted progressive/electronic improvisers Papadosio, who toyed with old school, elegant jamband time signatures and noted their excitement to finally play a Bonnaroo tent.

Appropriately enough during a week when Hillary Clinton became the first woman candidate to secure a nomination for a major political party, a number of standout early evening acts were female-fronted bands. They also all had something to say. Waxahatchee, the indie-pop act led by proud Alabama native Katie Crutchfield, discussed the festival’s importance in the South. Sultry-voiced Nashville alt-rock upstarts Bully reminded the audience that Bonnaroo was the first festival they played as a band shortly after their formation. Marian Hill, the collaborative project of Jeremy Lloyd (production) and Samantha Gongol (vocals), communicated through their influences, spiking their glitchy blend of hip-hop beats, pop and indie with a cover of Whitney Houston’s ‘80s single “I Wanna Dance with Somebody (Who Loves Me).” Even on the intimate Communion/Who Stage, sister act Joseph turned in a selection of harmony-heavy acoustic pop nuggets for an impressive late afternoon crowd. They also used the opportunity to debut a song from their forthcoming ATO release.

Elsewhere, grungy garage-rock group Twin Peaks celebrated their new studio effort Down In Heaven, producer and DJ “Uncle Jesse” Lauter dug into Prince’s catalog in the Silent Disco, and livetronica duo The Floozies took the stage to the Cantina theme song from Star Wars. Now that the U.S. album release day has been moved from Tuesday to Friday, Brooklyn country-blues rockers Mail the Horse officially dropped their new EP Magnoliaonstage at Bonnaroo after the clock inched past 12 a.m.

However, no band on the evening’s bill remained both as in the moment and decidedly Bonnaroovian as Vulfpeck. The Ann Arbor, Mich. outfit have gradually refined their mix of funk grooves, Zappa precision and theatrical stage antics since 2011 and, after a few choice festival victories, last night’s set felt like a true summer star coronation. They played by the Bonnaroo rules too, bringing out fellow Michigan performer BØRNS for an old-school sit-in on “Back Pocket” and dotting their setlist with covers like Al Green’s “Love and Happiness” and The Band’s “Up on Cripple Creek” (the latter of which featured the type of instrument swaps Levon Helm and his associates were known for, just with a much quicker pace). BØRNS kept that Bonnaroo spirit alive during his 10:45 p.m. slot, offering a cover of Arcade Fire’s Funeral classic “Rebellion (Lies)” that segued into David Bowie’s “Heroes.” It was comforting that those same stunts could have worked way back in 2002, albeit with different players, covers and segues.

In fact, as Bonnaroo’s 15-year-party really gets going, I’d like to propose a Disney-esque jingle, and possibly a request, courtesy of Saturday’s headliners Pearl Jam: “Everything has chains absolutely nothing’s changed.”