One night after a mind-blowing dinner at El Bulli last week I caught the opening stand of the new U2 tour in Barcelona.. The show was astonishing, the crowd and the venue equally so. Read my full report here.

It’s been a quarter century since I first fell for U2, upon hearing the title track from 1984’s The Unforgettable Fire—on vinyl, if that dates me even further. That song’s hypnotic arpeggios and triumphant, piano-driven chorus became my nightly fixation for the whole of freshman year of high school. If rousing anthems like “Out of Control” had made me swagger, “The Unforgettable Fire” made me swoon: it was love at first listen. For me, no band since—not R.E.M., not the Smiths, not the Replacements, not Radiohead—has even come close.

So I was pretty thrilled to find myself, 25 years later, at Barcelona’s Camp Nou (home turf of F.C. Barcelona, and the largest football stadium in Europe, with a capacity just over 100,000), mouth agape, as the band launched into a majestic rendition of “The Unforgettable Fire,” which they haven’t played live in almost two decades.

There were plenty of other highlights: a ragged-but-rousing version of the fan favorite “Party Girl” (during which a stunning Glamazon actually carried Bono across the stage); the first-ever live performance of the moody, haunting “Electrical Storm”; and seven songs off their ridiculously good new album, No Line on the Horizon. The Barcelona crowd—well-versed in the art of mass singalongs (“Oléeee, olé-olé-oléeeeee…”) and still giddy from Barça’s Champions League victory last month—were in a frenzy for the entire two-and-a-half-hour set. But for me the peak moment came during the opening bars of “Sunday Bloody Sunday,” when the stage was bathed in beautiful green light and Farsi script began scrolling across the screen above. My wife Nilou (born and raised in Tehran) recognized it as the first stanza of “The Reed Flute’s Song,” by the Persian poet Rumi—a heartbreaking lament of separation and loss. For perhaps the first time ever, Bono didn’t have to say a word; the crowd recognized this moving tribute to the democratic movement in Iran.

The band, it turned out, were encamped a few floors above us at Barcelona’s Hotel Arts, and had spent the past two weeks rehearsing at Camp Nou (and, apparently, eating their way across Barcelona: Bono had dinner at the fabulously inventive Möo the night after we went).

Ken Friedman, owner of New York’s Spotted Pig and a longtime friend of the band, kindly set us up with backstage passes and invitations to the hotel after-party, at which a giant cake in the shape of the stage (above) was unveiled, complete with Bono, Edge, Adam, and Larry figurines. This tour’s stage design is the band’s most spectacular yet, and that’s in a long line of spectacular stage sets—the mile-high tower of light that beamed up from the stage during “City of Blinding Lights” was breathtaking.

U2’s 360 Tour rolls into 14 cities in Europe this summer before arriving stateside in September; many shows are sold out, but some stray tickets and travel packages remain. If you’re able, by all means go—this is among U2’s finest moments, and arguably the only show worth seeing from even the back row of a stadium. In short: unforgettable.

Peter Jon Lindberg is Travel+Leisure's editor at large.