Hundreds of Beatles fans swarmed Abbey Road on Saturday, singing songs and snarling traffic to mark 40 years since John, Paul, George and Ringo strode across the leafy north London street and into the history books on iconic pop photos.

The famous photo graced the cover of the Fab Four's Abbey Road, the last album recorded together, and shows the bandmates walking purposefully across the zebra-striped asphalt.

It remains one of music's best-known album covers, endlessly imitated and parodied. Although the shoot itself only took a few minutes, so carefully studied was the cover for signs and symbolism that some diehard fans came to the conclusion that Paul McCartney - who appears barefoot and out of step with the rest - had secretly died.

McCartney himself made fun of the bizarre conspiracy in the title of his 1993 concert album, Paul is Live.

Shrine to the Beatles

Conspiracies aside, the ease with which fans can imitate the scene has drawn throngs of tourists to the site every day, turning the street into "a shrine to the Beatles", said Richard Porter, who owns the nearby Beatles Coffee Shop and organised Saturday's event.

Crowds spilled into the street, cameramen jostled for angles and exasperated drivers honked their horns.

"I didn't expect so many people to be here," said German visitor Tschale Haas, 50, who was dressed in a Sgt Pepper jacket.

Abbey Road, which cuts through London's well-to-do neighbourhood of St John's Wood, is home to the eponymous studios where the group recorded much of its work.

The group decided to shoot the photograph in August 1969 while recording music for the last time together. For the shot, photographer Iain Macmillan stood on a stepladder and police held up traffic while the Beatles walked back and forth across the street.