Bands occasionally thrill the fan base by playing an entire classic album, as U2 did to mark the 30^th anniversary of The Joshua Tree with Sunday’s stadium-wide airing in Foxboro. But Wilco went an inclusive step further, letting fans vote online for their pick to launch the Chicago band’s biennial Solid Sound Festival in North Adams over the weekend. Perhaps fans simply wanted the longest record, as the 1996 double album Being There out-polled 2002 landmark Yankee Hotel Foxtrot.

In any case, Wilco surprised them on Friday night, following a full reading of Being There with an encore of Yankee Hotel Foxtrot, also in its entirety – a sublime 30-song marathon of its two best albums, for a largely awestruck crowd of 8,500 who packed the field outside MASS MoCA.

“This is what we’re supposed to do,” Wilco leader Jeff Tweedy told the crowd that returned for Saturday’s headlining set, as the group met the challenge of tapping its remaining catalog for another 29 songs across two and a half hours. “Keep each other inspired.”

Julian Lage with Wilco’s Nels Cline

Dave and Phil Alvin

But he wasn’t just talking about Wilco’s performance, since Solid Sound’s about so much more than its host band. There isn’t another festival in the Northeast — or beyond — that offers such a novel, inclusive vibe, extending to musical styles from traditional folk and roots-rock to neo-punk and avant-jazz. Chalk up much of that magic to the unique infrastructure of MASS MoCA, which gave music fans the run of its expanded warehouse-sized galleries, which surround courtyard stages and lend space for intimate (if quickly crowded) pop-up sets by fest performers. Wilco guitar virtuoso Nels Cline and his wife Yuka Honda from Cibo Matto etched soundscapes in one pop-up, while another found “Parks and Recreation” actor Nick Offerman (one of the comedians assembled by John Hodgman for indoor Hunter Center sets) playing acoustic guitar to sing Tom Waits’ “Innocent When You Dream.”

Outsider folk-pop combo the Shaggs (surviving sisters Dot and Betty Wiggin, plus backing musicians) reunited for the first time since 1999 for a purposely off-key but charming set of songs from their 1969 cult album Philosophy of the World plus a cover of Marie Osmond’s “Paper Roses.” Steered by guitarist/singer Tom Verlaine, CBGBs proto-punk legends Television delved into skeletal jams more akin to the Grateful Dead before closing with the transcendent “Marquee Moon” (which Wilco played in a covers set at 2013’s Solid Sound). Phil and Dave Alvin rocked with roots outfit the Guilty Ones, peaking with their Blasters-era nugget “Marie Marie,” and the Robert Glasper Experiment (fronted by Casey Benjamin on keytar and sax) mixed funky breakbeats with soul-jazz. Adrianne Lenker deeply inhabited her songs with ghosty folk-rockers Big Thief, and re-bearded Boston icon Peter Wolf (whose link to Wilco was recording in the band’s Chicago studio) had the museum’s larger courtyard in the palm of his beat-pumping hands.Late nights were capped by the Alloy Orchestra accompanying silent 1920s films in the Hunter Center, while the courtyard split Friday and Saturday between the jazz of the minimalist Dawn of Midi and the ruminative Jeff Parker Trio. Sunday provided a more relaxed schedule with several Wilco side projects, peaking with the edgy improvisation of the Nels Cline Four, where Cline traded mesmerizing guitar tendrils with foil Julian Lage. In turn, West Coast sax veteran Idris Ackamoor arrived on the main stage in pharaoh’s headpiece to led his group the Pyramids in spirited, ’60s-futuristic Afro-jazz before a more laidback Tweedy closed out the fest with his self-named side project featuring son Spencer on drums.

The Shaggs

Peter Wolf

As for Wilco’s sets, Friday was hard to beat with the two complete albums. Being There, the bridge between the band’s alt-country roots and more experimental future rock, alternated somber, folky fare (notably “The Lonely 1,” despite some distraction from a distant courtyard soundcheck) with groove kickers “Kingpin” and “Dreamer in My Dreams,” respectively channeling Little Feat and the Faces.

Songs from both albums remain in varying degrees of live rotation for Wilco, but it was great to hear them in sequential context, especially Yankee Hotel Foxtrot, which includes popular numbers “War on War,” “Jesus, Etc.” and “Heavy Metal Drummer.” That album proved a more cohesive artifact of its time, reflecting 9/11 in the mournful reflection of tracks like “Ashes of American Flags,” even though it was recorded before those attacks. And Wilco crammed it in at a relaxed pace, with Cline scintillating throughout, though Tweedy ripped gnarly fuzz with his own leads on “I’m the Man Who Loves You” – egged on by standout drummer Glenn Kotche, who stood on his stool with sticks in the air to cue a rock-god salute.

Saturday proved more of a mixed bag momentum-wise as a freer-wheeling Wilco dug deep. Cline manically pogoed during a few of his solos, and fans – who came from around the country — loudly sang along to “Via Chicago” (the band thrashing dissonant bursts against Tweedy’s twangy strum, only to end in pinpoint stops), “Hummingbird” and the riff melody of Krautrock jam “Spiders (Kidsmoke).”

It didn’t hurt that the weekend’s weather was perfect (beyond a few sprinkles) and that the museum’s exhibit space has only expanded, highlighted by Laurie Anderson’s “Chalkroom” (a mind-blowing virtual reality trip requiring advance reservations) and visual artist Nick Cave’s “Until,” filled with curtains of 16,000 wind spinners among other sculptures. If you want a good excuse for a trip to the Berkshires with music and art in mind, MASS MoCA hosts Joan Osborne playing Bob Dylan songs on July 7, the Bang on a Can Marathon (including works by Steve Reich and Louis Andriessen) on Aug. 5, My Morning Jacket on Aug. 12, and the FreshGrass Festival (Brandi Carlile, Del McCoury Band, Railroad Earth, Bill Frisell, etc.) on Sept. 15-17. Alas, you’ll have to wait another two years to look for Solid Sound to return for its sixth edition.