It's been over four decades and the lyrics still don't make much sense - what is a "bustle in your hedgerow" anyway? - but there's probably never been a song with such chart-topping impact. All the more incredible, since Stairway to Heaven was never released as a single.
So love 'em or hate 'em, Led Zeppelin simply have to go down as one of the most successful and influential bands in the history of rock music.
When The Yardbirds broke up in 1968, Jimmy Page formed The New Yardbirds (Zep's working title), first recruiting John Paul Jones, another respected session player, on bass and keyboards.
Initially they had Terry Reid in mind as the singer, but when he declined a friend recommended Birmingham-based Robert Plant. Plant was singing in a group called Hobbstweedle (remember them?) and also provided drummer John Bonham (the pair had previously played together in a band called Band of Joy).
Their first British tour won them few friends, and they immediately decided to focus on the American market, where page's reputation had greater cachet and other British bands like Cream and The Jeff Beck Group had made considerable impact.
By their second tour they had an impressive debut album in tow.
The band recorded their first album (Led Zeppelin I) in 30 hours. The record set a standard in high-energy rock that has been rarely surpassed but often imitated. By early 1969 it was in the US Top Ten album chart.
Led Zeppelin II (1969) was in much the same vein, and when critics dismissed Zep as blustering rock bozos, the band retreated to Bron-Yr-Aur, a cottage in Snowdonia, North Wales, that Plant had often visited as a child.
With no electricity or running water, they spent days walking in the hills and nights sitting around the fire plunging hot pokers into cider, smoking hash and writing.
So important was the cottage and its setting that not only did they write a song about it (Bron-Y-Aur Stomp), but gave it a thank-you on the cover of the subsequent album, Led Zeppelin III (1970), which was filled with acoustic subtlety. The critics - never satisfied - accused them of going all Crosby, Stills & Nash . . .
Their fourth album broke a few rules - Its sleeve carried no band name and no title, just four Runic symbols.
The album contained Stairway To Heaven, the song which became so entrenched as a rock standard that to this day many guitar shops carry signs prohibiting it being played on their premises!
They planned their 70's career extremely carefully, releasing one album a year and timing their tours to build anticipation for it, never performing on TV (apart from one appearance in their first year), and never releasing a single in the UK until 1997.
Their rise - rapid and phenomenal - attracted the disdain of music critics, who never acknowledged the excellence of some of their ensuing albums, particularly IV (1971) and Physical Graffiti (1975), which were surprisingly diverse in content.
Led Zeppelin's IV practically defined hard rock and heavy metal. It drew on folk music, the blues, rock & roll, and even psychedelia. But it was also the sound of a band grooming themselves for stadium success.
The album's mystique was increased by its cover, which features no group name or album title, hence its alternative monikers "Four Symbols" and "Zoso", a reference to the runic symbols displayed within the gatefold.
The band formed their own label in 1974, called Swansong. The launch of the label was held at Chiselhurst Caves in Kent, England, on Halloween. Drinks were served by nuns in suspenders, a naked woman lay in a coffin covered in jelly, and naked male wrestlers cavorted in recesses of the caves . . .
By the mid-70s Led Zeppelin were arguably the most successful group in the world and offered a blueprint for all the subsequently successful British metal acts, such as Black Sabbath, Deep Purple, Ten Years After and, more recently, Rainbow.
No other group has sustained such a huge following for so long by repeatedly withdrawing from the limelight and then returning with a near-perfect master plan.
By late 1979 it had been four years since Led Zeppelin's last studio album and three years since their last tour. The public's appetite was whetted for something new, and In Through The Out Door - recorded in a mere three weeks at ABBA's Swedish studio - entered the album charts at #1. The album would turn out to be their swan song (no pun intended).
On 25 September 1980, on the eve of their US tour, drummer John Bonham was found dead in bed in Jimmy Page's house in Windsor, England, after a 12-hour drinking session. The autopsy reported the cause of death as pulmonary oedema. He was only 32.
Apparently, the unstoppable Bonham had downed some 40 measures of vodka before quite literally calling it a day.
Before becoming Led Zep's manager and terrifying hapless promoters around the world, Peter Grant was a professional wrestler who went by the name of His Highness Count Bruno Alassio of Milan. He also body-doubled for Anthony Quinn in The Guns Of Navarone (1961).