To mark the occasion, hundreds of fans gathered at the spot, in St John's Wood, not far from Lord's cricket ground, to mark the occasion.
The photoshoot for The Beatles' 1969 album Abbey Road occurred just a few minutes' walk away from the world famous Abbey Road Studios.
But a conspiracy theory surrounds the photo.
Many Beatles fans believe that Paul McCartney was killed in a car crash in 1966, so the one walking across a zebra crossing in August 1969 was an imposter.
They believe The Beatles regretted pulling the wool over the fans' eyes by pretending he was the real Paul, and so placed hidden clues on the album cover for their fans.
According to the conspiracy theorists, the procession of The Beatles across the zebra crossing represents Paul's funeral.
But that's not the only bizarre theory surrounding the Abbey Road album. Here are the others.....
Pictured: The Beatles album cover that started a decades-long conspiracy theory
By Mail On Sunday Reporter
09th August 2009
Forty years ago yesterday, at 11.35am, The Beatles walked across a zebra crossing in an innocuous North London street.
The photoshoot for their new Abbey Road album happened just yards from the eponymous recording studios and took ten minutes - only six frames were taken by the photographer, Iain Macmillan, who was perched on a stepladder.
It has since become one of the most iconic covers in history for two reasons - no album cover has inspired more imitations, and none has spawned such a mass of conspiracy theories.
CLICK ON ALL PICTURES TO ENLARGE
The Beatles' world-famous Abbey Road album cover that sparked a million conspiracy theories. The location was St John's Wood, north London. The date: 8th August 1969
For Beatles obsessives with fevered imaginations, it was ultimate proof of the bizarre theory of the time - that Paul McCartney was, in fact, dead.
According to the legend, Paul had died in a car accident and been replaced by an impostor. The band, it was said, subsequently felt guilty about the deception, and so placed hidden clues on the album cover for their fans.
Thus, even today, despite the apparent rude health of McCartney, they insist that if you look closely at the images on the front and back of the album it is packed with deathly symbolism.
Beatlemania: A tribute band joined hundreds of fans in Abbey Road yesterday to celebrate the 40th anniversary of the famous photoshoot
Surrounded: A bus comes to a standstill as fans mob the Abbey Road site
What is certain is that the album denoted one death of sorts.
Unbeknown to the public at the time, The Beatles were in the final throes of a bitter break-up and would never record another album.
Relations had deteriorated to such an extent that the group abandoned their original title of Everest, together with a shoot in the Himalayas, and were photographed instead walking away from the studios and everything they had once shared.
For other devotees, however, far more could be read into the image (shown above, and is numbered)...
1. THE FUNERAL
The procession of The Beatles across the zebra crossing, say the conspiracy theorists, represents Paul's funeral.
John Lennon leads in a white suit and symbolises the preacher; Ringo Starr is the mourner, dressed in black; George Harrison, in scruffy shirt and trousers, denotes the grave-digger; Paul is wearing an old suit and is the only one who is barefoot.
He later explained that he began the shoot wearing sandals but, because it was a hot day, he kicked them off.
The theorists believed that if this was the case, the hot tarmac would be too uncomfortable. This, they argued, was a sign that Paul was the corpse.
2. THE CIGARETTE
Paul McCartney is left-handed, but here holds his cigarette in his right hand. At the time, cigarettes were commonly referred to as 'coffin nails'. This, therefore, could be seen as a message that Paul's 'coffin lid' had been nailed down and that the man in the picture was a lookalike.
Paul is also out of step with the other band members. Each of the others has his left leg forward, but Paul has his right leg forward - again marking him out as different.
3. THE REGISTRATION PLATE
The white VW Beetle in the background has the registration LMW 28IF - 28 being the age conspiracy theorists say Paul would have been IF he hadn't 'died'.
In fact, Paul was 27 when Abbey Road was released - but fortunately for the theorists, Indian mystics count a person's age from conception, not birth, in which case Paul would have indeed been 28 at the time.
Besides, the band were famously followers of the Indian guru, Maharishi Mahesh Yogi. It has also been suggested that the LMW stands for 'Linda McCartney Weeps' - referring to his new wife whom he had married earlier that year.
4. THE SPECTATORS
In the background, a small group of people dressed in white stand on one side of the road, while a lone person stands on the other.
Is this meant to be Paul, alone and different from the others?
5. THE POLICE VAN
On the right-hand side of the road is a black police van, believed to be a reference to the police who kept quiet about Paul's 'death'.
According to legend, the band's manager, Brian Epstein, bought their silence, and the presence of the Maria is meant as another subtle thank you.
6. THE LINE OF CARS
A line can be traced from the VW Beetle to the three cars in front of it. If it is drawn connecting their right wheels it runs straight through Paul's head, with theorists suggesting that means Paul sustained a head injury because of a car crash.
7. THE BLOODSTAIN
On the Australian version of the album, the cover showed what could be a bloodstain splattered on the road just behind Ringo and John, supposedly backing claims of a road accident.
8. THE CRACKED S
On the back cover (shown below) there is a picture of the Abbey Road sign and above it the name Beatles has been written. There is an obvious crack running through the S - thought to suggest problems within the group.
9. THE DOTS
To the left of the name 'BEATLES' there are a series of eight dots. When joined together they form the number three.
Did this mean there were only three Beatles left?
10. IMAGE OF DEATH
If the back cover is turned 45 degrees anticlockwise a crude image of the Grim Reaper appears, from his skull to his black gown. Theorists believed it was a sign that someone in the group had died.
11. THE GIRL
Nobody knows the identity of the girl dressed in blue on the back cover. On the night of the theorists' 'car crash' it was raining heavily and Paul is said to have given a lift to a fan called Rita. It could be that this girl is her, either fleeing the scene or running to get help.
12. PAUL'S FINAL RESTING PLACE
If the writing on the wall is split into sections, it conveys the cryptic message, 'Be at Les Abbey'. In numerology the following two letters, R and O, are the 18th and 15th letters in the alphabet. By adding this together (33) and multiplying by the number of letters (2), we get 66, the year Paul is supposed to have died.
Three also represents the letter C so 33 could also stand for CC. Cece is short for Cecilia, with theorists claiming Paul was 'laid to rest' at St Cecilia's Abbey, a monastery in Ryde, Isle of Wight.
The back cover