Jerry Garcia is soaring.

What else would you expect at the Fillmore, San Francisco’s most illustrious rock-concert venue?

We’re not talking about a hologram, a la Michael Jackson at the Billboard Music Awards.

Climb the stairs to the Fillmore’s legendary poster rooms and, on the landing, there’s a photo of Garcia, with one of those Captain Trips smiles in mid-guitar solo, enshrined in a fancy gold-embossed triptych frame. That classic image gets you in the mood for the two upstairs poster rooms, which feature framed posters for just about every concert ever held in this auditorium since 1965.

Seriously. Every concert, a poster. Not photos but artistic drawings and designs. In every color imaginable. Psychedelic doesn’t begin to describe it. You could get high just off the fumes caked on these posters.

Joplin, Hendrix, the Dead, Tom Petty’s 20-show marathon, Willie Nelson, Dave Chappelle.

Look carefully and you’ll even find Minneapolis’ own Semisonic on one of the posters that is strangely horizontal on a wall of vertical images. Go figure. It’s from 2001.

“It was a huge thrill” to play there, said Semisonic bassist John Munson, who had been fully aware of the venue since a late 1960s family trip to the West Coast on which his older brother got to see Janis Joplin at the Fillmore. “It’s a very classy outfit. You take one of those posters home. I have a copy of the poster in a scrapbook.”

Among the more than 1,400 posters, some commemorate historic rock moments. Like one with the Buffalo Springfield, featuring Neil Young and Stephen Stills, on the same bill as Hour Glass, featuring then-unknowns Duane and Gregg Allman. Or Led Zeppelin opening for Country Joe and the Fish.

“The poster art looks like the music sounded,” said veteran San Francisco critic Joel Selvin, who has been covering the music scene since 1969.

Unfortunately, the Fillmore ran out of wall space in 2007. But the staff still creates a poster for every gig.

Opened in 1912

The Fillmore — which is open only for concerts, not guided tours — is a pretty trippy place. The beige brick exterior is nondescript, and the lighted marquee is actually over the business next door, a loan and check-cashing joint.

The interior of the music room feels a bit like it’s decorated in Gold Rush bordello, with dark-red velvet curtains and dusty chandeliers from another decade.

If you land one of the seating boxes in the balcony, you get a bird’s-eye view of the flashy light show, the happy crowd and the musicians onstage. This place feels like a repurposed ballroom.

In fact, the building at the corner of Fillmore Street and Geary Boulevard opened in 1912 as Majestic Hall and Majestic Academy of Dancing, home to masquerade balls and other social events. The name of the venue changed over the years but dancing and entertainment were the bill of fare. In the 1940s, the place was a roller rink. In 1952, a local promoter started booking R&B artists, including Ike Turner and James Brown, and renamed it the Fillmore.

On Dec. 10, 1965, as San Francisco emerged as a hot spot for hippies and the counterculture, promoter Bill Graham presented a benefit for the San Francisco Mime Troupe featuring the Jefferson Airplane and the Grateful Dead.

The Fillmore not only helped launch such Bay Area bands as Santana and Big Brother and the Holding Company (featuring Joplin), but it became the place to play for such touring stars as the Who, Muddy Waters and Jimi Hendrix (who infamously opened for the Monkees at the Fillmore in ’67) as well as comedians like Lenny Bruce and poets like Allen Ginsberg.

The concerts featured far-out light shows, uninhibited dancing and whatever turned young people on at the height of counterculture.

In 1968, Graham relocated the Fillmore to a better neighborhood, dubbing it the Fillmore West (he also operated a Fillmore East in New York City). He closed the West Coast place in ’71.

In the 1980s, the original Fillmore became the Elite Club, a punk-rock club, before the 1989 earthquake forced its closing. Five years later, it reopened as the Fillmore once again with the Smashing Pumpkins.

The current schedule remains remarkably eclectic. In June, performers include R&B star Kelis, reggaeton hero Yandel, indie-rock darlings TuneYards, jazz-pop pianist Jamie Cullum, British electronica act Metronomy and retro soul man Lee Fields.

Over the years, some classic live albums were recorded at the Fillmore, including those by Aretha Franklin, Miles Davis, King Curtis, Traffic, Cream and, more recently, Lucinda Williams.

‘Hallowed hall’

With a capacity of 1,100, the Fillmore, now run by the world’s biggest promoter, Live Nation, is still the prestigious place to play in San Francisco.

“For our kind of music, it’s the hallowed hall where it all got started,” said Jeff Mattson, guitarist/singer for Dark Star Orchestra, a Grateful Dead tribute band that has performed at the Fillmore several times. “There’s a cultural touchstone in that word ‘Fillmore,’ associated with the music I grew up listening to. Every third album I bought was ‘Live at the Fillmore.’ There’s just a great vibe in that room. You sort of feel the ghosts of all the performances that played there. … I strongly feel the history of the place.”

The sense of history is captured near the dance floor in large, framed photos of Miles, Janis and the early Dead with a clean-shaven Jerry Garcia. There’s also room for something completely new at the Fillmore — little-known solo acts and duos playing acoustic music on a tiny stage in one of the poster rooms during intermission in the main hall.

At the end of the night, two traditions carry on in the grungy foyer: free posters and apples as you exit. Graham himself used to hand out apples back in the day. Maybe after all that music (or pot), music lovers are hungry. Or maybe they’ll just want to pass the apple to one of the many homeless young people who hang out outside the Fillmore.