It is the Mona Lisa of rock albums, the one that elevated pop music to fine art. No album has been more scrutinized, analyzed, evaluated, parsed, written about and enjoyed.

It is, of course, the Beatles' masterpiece, Sgt. Pepper's Lonely Hearts Club Band.

Growing up in the '70s, visiting a friend's house meant listening to various permutations of John Denver, Neil Diamond and the Monkees, not to mention what ever Top 40 junk your friend was into that week. A play date could be pretty musically grim.

The good news, though, was that every kid had a copy of Sgt. Pepper in his stacks. The album was old reliable, the soundtrack to countless Hot Wheels races and Evel Knievel Stunt Cycle mishaps.

When Sgt. Pepper turned 20 years old on June 1, 1987, I was 20, too. I remember staring at the CD long box, marveling at the album's longevity: How in the world did it remain so popular now that the two of us were so impossibly old?

Now here we are, another 28 years gone and the Beatles' masterpiece still regularly tops the "greatest all-time albums" lists. Occasionally, it is bumped by its greatest influence, the Beach Boys' Pet Sounds, but nearly 50 years on the general consensus remains that Sgt. Pepper's Lonely Hearts Club Band is a towering achievement.

So what the heck am I, a lowly music writer, going to tell you that you don't already know? What can I possibly say that academics, critics and the people who were there haven't already said?

Absolutely nothing, so I'm not even going to try. Instead, I'm going to pony up a few tidbits that you may not know about Sgt. Pepper. Or maybe you do, I don't know. Listen, the only thing I'm sure about is that it's my turn to wind up the Evel Knievel Stunt Cycle, so move over.

1. The album cover depicts a funeral scene.

The Beatles retired the whole "lovable mop tops" bit after their 1966 tour, and what better way to say goodbye than with a funeral? Note that "Beatles" is spelled out in funerary flowers in the photograph and "Sgt. Peppers Lonely Hearts Club Band" appears on the bass drum -- the new band is saying so long to the old band.

Bonus fact: The actual photo shoot only took three hours.

2. Beatles manager Brian Epstein hated the now famous album cover.

Maybe he was still reeling from the "butcher cover" incident a year earlier; regardless, Epstein went so far as to suggest that the album be shipped in a plain brown wrapper.

3. The back cover includes the band's first printed reference to Apple.

Apple Records didn't make its debut until December 1967, but the back sleeve of Sgt. Pepper gives joint credit for the cover to "M C Productions and The Apple."

4. Each band member wears his MBE on the front cover.

The Beatles were the first rock band to be honored by the Queen as "Members of the Most Excellent Order of the British Empire," or MBEs. This was a political move by British Prime Minister Harold Wilson to appeal to the nation's youth, but it opened the door to the endless sea of Sir Rock Stars that we see today.

5. The album's first single doesn't even appear on the album.

The band spent 105 hours recording the double A-side single, "Penny Lane/Strawberry Fields Forever." Released in February 1967, it stalled on the U.K. charts at No. 2, provoking much speculation in the press that the Beatles were done. That's right: Hitting No. 2 meant they were washed up -- talk about first world problems.

Manager Brian Epstein exerted pressure not to include the two classic tracks on the album -- a decision with which producer George Martin allegedly disagreed and later regretted.

6. Paul and Linda became "Paul and Linda" at the album's launch party.

Well, sort of. The two actually met four days earlier, but if you think in terms of two people crossing the threshold separating platonic friendliness and amorous interest, this is the night it happened.

7. "Lucy in the Sky with Diamonds" really was based on a drawing by John's son, Julian.

This remains the Sgt. Pepper fact that we all refuse to believe, so it's worth restating here: One of John Lennon's most psychedelic songs is not titled after LSD. Little Julian, all of four years old at the time, came home from preschool with a drawing of his friend, Lucy O'Donnell. When his father asked him to explain his work, the boy described it as "Lucy, in the sky, with diamonds."

The drawing still exists, and O'Donnell didn't know that she was the subject of a Beatles classic until she was 13 years old.

8. "She's Leaving Home" was based on a real person, too.

Paul McCartney wrote this track after reading an article about a 17-year-old girl named Melanie Coe who ran away from home. Maca made up his own story loosely based on a quote from Coe's father: "I cannot imagine why she should run away. She has everything here."

Remarkably, he got the real life story fairly right. Ms. Coe is quoted in Steve Turner's The Beatles: A Hard Day's Write as saying:

The amazing thing about the song was how much it got right about my life. It quoted the parents as saying 'we gave her everything money could buy,' which was true in my case. I had two diamond rings, a mink coat, hand-made clothes in silk and cashmere and even my own car....

Bonus fact: Melanie Coe actually met the Beatles almost four years earlier after winning a mime competition on the television show Ready Steady Go!

9. "With a Little Help From My Friends" started life as "Bad Finger Boogie."

That in itself isn't a particularly interesting bit of a trivia, but here's where it makes an interesting footnote: A couple of years later the Beatles signed a band named the Iveys to Apple Records, and Lennon suggested that they change their name to Badfinger.

If the following track sounds Beatles-esque to you, there's a reason: Paul McCartney wrote it.

10. Paul wrote "When I'm Sixty-Four" when he was 15, released it when his father was 64.

The song dates to the Quarry Men days, the band that would evolve into the Beatles. McCartney used it as a time filler when the band lost power or had other technical issues during those early gigs.

11. "Being for the Benefit of Mr. Kite!" was based on a Victorian circus poster.

Lennon picked up an old circus poster in an antique shop and hung it in his music room. The poster, printed in 1843, announces that "Pablo Fanque's Circus Royal" will hold the "Grandest Night of the Season....Being for the Benefit of Mr. Kite." It notes that the Hendersons will be there, too.

These were all real people who were quite famous in the circus world of their time, but with a little reworking Lennon turned them into a song that he referred to as "so cosmically beautiful ... like a painting, a pure [watercolor]."

Copies of the poster are readily available on the internet.

Bonus fact: Pablo Fanque (real name: William Darby) was the first black circus proprietor in England.

12. "Good Morning Good Morning" took both its chorus and title from a Corn Flakes commercial.

Here's yet another example of Lennon elevating the mundane to art.

13. "A Day in the Life" marks the first time that separate Lennon and McCartney songs were welded together.

The Beatles (including producer George Martin) were wonderfully innovative, making the most of everything. During the Revolver sessions two unfinished Lennon songs were merged together to create "She Said She Said." As brilliant as that track is, this collage approach didn't reach its zenith until the Sgt. Pepper sessions.

Paul's song fragment happened to fit perfectly after what during the song's construction was 24 empty bars counted aloud by road manager Mal Evans. At the end of the "empty" section, Evans set off an alarm clock to note where the band would eventually come back in, and wouldn't you know it -- Maca's "Woke up / got out of bed" verse fit as if the whole thing was planned.

Bonus fact: All four Beatles did not simultaneously play an E-major chord at the climax of the song. John, Paul, and Ringo did, but road manager Evans is the fourth player, not George.

With Sgt. Pepper, did the Beatles want to "turn you on," as Lennon sings in "A Day in the Life"? Absolutely. In 1968, McCartney said that "what we want to do is turn you on to the truth rather than on to pot."

The album turned us on to so much more than that. For many of us the Peter Blake album cover was our introduction to pop art, and the many faces in the cover photo led to hours of poring through encyclopedias for more information. The notion of a cohesive concept tying an album together didn't originate with the Beatles, but the overwhelming majority of listeners were introduced to the idea of a concept album via Sgt. Pepper.

Songs made from everyday things, found sounds turned into music, the realization that a band was at some level four guys playing characters -- Sgt. Pepper's Lonely Hearts Club Band turned us on to all of that and more on June 1, 1967 ... and every day for the last 48 years.

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