The Beatles’ discography has been dissected and inspected ad nauseam, and the highlights of their musical legacy have been absorbed by millions of fans. But 50 years after the release of the last album they’d record as a group, it’s still staggering how much ground they covered in under a decade. It’s also impressive that their final run together works so perfectly as the culmination of their greatness—a perfect benediction for what must’ve been one wild, unexpected, and creative ride. Abbey Road remains a masterpiece.

The Beatles’ final album is their strongest and the best summation of the foursome’s best qualities. Revolver may be their most unequivocally groundbreaking, but rock music had continuously pushed forward so consistently in the years since that it sounded like old hat by 1969. Sgt. Pepper’s Lonely Hearts Club Band may be their most historically important, but its mythological reputation belies a collection of songs that can often feel middling and indulgent compared to their other work. And The Beatles (aka “The White Album”) is such a behemoth that it can’t help but contain many of their most scattershot moments as a collective. But Abbey Road has the inspired creativity of Revolver, the faux-conceptualism of Sgt. Pepper’s, and the individual brilliance of “The White Album”—all delivered with a production flair and instrumental gloss that suggests the band knew this was their last chance to be their best selves.

As with virtually every Beatles’ album after 1966, Abbey Road feels like a McCartney-driven affair. The famous song suite that dominates its second half has the hallmarks of his forthcoming Wings-era: sonic pomp undercutting lyrical inanity; a breadth of disparate ideas melded into one thrilling musical statement. But John Lennon’s presence on the album is formidable. It goes under-discussed just how much Lennon’s heroin addiction affected his waning months within the Beatles, and his somewhat diminished presence across both the Let It Be and Abbey Road projects belies a man who had one foot out the door. Lennon’s attention was being pulled by heroin, his irritation with battling McCartney over business, and his intense affair-turned-marriage to Yoko Ono. His songwriting was the lifeblood of the Beatles circa 1964-1966, and his bold creativity informed their 1966 transformation from pop idols to studio innovators. By 1969, distracted as he was, Lennon was still an essential part of this band. His standouts—the sludgy hard-rocking classic “I Want You (She’s So Heavy)” and elaborately harmony-driven “Because”—are two of the best moments on Abbey Road, and his contributions to the album’s second half are indispensable. New light has been shed that reveals that Lennon was more into the quasi-operetta half of the album than fans have thought over the years, but in the immediate aftermath of the album’s success, he was dismissive.

“I liked the A side,” John Lennon would tell Rolling Stone in 1970. “I never liked that sort of pop opera on the other side. I think it’s junk. It was just bits of song thrown together. And I can’t remember what some of it is.”

“The two of them were on heroin,” said McCartney years later of John and Yoko during the sessions, “And this was a fairly big shocker for us because we all thought we were far-out boys, but we kind of understood that we’d never get quite that far out.”

“ The two of them were on heroin. And this was a fairly big shocker for us because we all thought we were far-out boys, but we kind of understood that we’d never get quite that far out. ”

McCartney’s reputation for meticulousness and craft is well-earned on Abbey Road. Of all the principals involved, it sounds most like Paul. His workhorse nature would sometimes cause rifts within the band (Harrison and Ringo Starr reportedly hated working endless hours on the daft “Maxwell’s Silver Hammer,” while Lennon didn’t play on the track at all) but when it worked, his vision could push the band to its highest heights—as on the stellar one-two punch of “Polythene Pam” and “She Came In Through the Bathroom Window.” And his creative bass playing is one of the album’s delights; it’s Paul’s bass that truly elevates Lennon’s Chuck Berry-nicking hit “Come Together,” and it’s the secret pulse of Harrison’s “Here Comes the Sun.”

Ringo Starr’s only written contribution to the album was technically a co-write with George, but “Octopus’ Garden” is the kind of winning kiddie singalong that’s endearing, as opposed to irritating a la “Yellow Submarine,” and Starr’s unique drumming is another one of the album’s strengths. It’s Ringo’s different strokes that color and re-color “…She’s So Heavy,” and that propels the band through the musical shifts of the album’s second half.

It’s Harrison’s guitar that serves as a binding element throughout the album. His playing is the most fluid and assured it would ever sound on a Beatles’ record; from the soaringly melodic solo on “Something” to the arpeggiated leads on “Sun King,” Harrison’s confidence is as evident as Lennon’s apathy. Much is made of George’s “emergence” on Abbey Road, although his talents had become more and more evident within the Beatles (and via his production work outside the group for acts like Billy Preston and Jackie Lomax) for years. But he’d gotten sour on the Fab experience far earlier than his bandmates, and sometimes his indifference showed in how little he participated in certain albums—like Sgt. Pepper’s. But since he’d gotten over his mid-‘60s sitar fixation and renewed his focus on guitar playing in 1968, Harrison had grown by leaps and bounds. And as a songwriter, the twin standouts of “Here Comes the Sun” and “Something” put him squarely in league with his more celebrated bandmates.

“I wasn’t Lennon or I wasn’t McCartney. I was me,” Harrison told the BBC a few days after the album’s release. “And the only reason I started to write songs was because I thought, well if they can write them, I can write them. You know, ‘cause really, everybody can write songs if they want to. If they have a desire to and if they have sort of some musical knowledge and background. And then it’s by writing them the same as writing books or writing articles or painting—the more you do it, the better or the more you can understand how to do it. And I used to just write songs. I still do. I just write a song and it just comes out however it wants to. And some of them are catchy songs like ‘Here Comes The Sun’ and some of them aren’t, you know. But to me there’s just songs and I just write them and some will be considered as good by maybe the masses and some won’t. But to me they’re just songs, things that are there that have to be got out.”

When asked if he considered himself a late-bloomer, Harrison’s response was typical George: “What’s late and what’s early?”

Abbey Road’s sonic texture falls just shy of gloss—the kind of overdubbed and streamlined sound that would come to define classic rock albums of the 1970s. Criticized by some reviewers at the time for its emphasis on “electronics,” it’s the Beatles at their most polished and their most contemporary. And their most final.

A month after the album’s release and while it was still at No. 1, McCartney would somewhat nonchalantly announce the end of the band in an interview with Life.

“I would rather do what I began by doing, which is making music. We make good music and we want to go on making good music. But the Beatle thing is over. It has been exploded, partly by what we have done, and partly by other people. We are individuals—all different. John married Yoko, I married Linda. We didn’t marry the same girl.”

But The Beatles’ breakup wouldn’t become public knowledge for almost another six months, though they would never enter the studio again as a group after fall 1969. Some overdubbing for the Get Back project (released somewhat posthumously in 1970 as the band’s final album, Let It Be) would be the last time they worked on anything Beatles-related until Harrison, McCartney and Starr partnered up for 1995’s Anthology. For all intents and purposes, Abbey Road was the end. And given what they were able to accomplish on this record, they couldn’t have given the world a better farewell.