By January 1975, Led Zeppelin had firmly established themselves as the biggest rock band on the planet. Though they hadn’t garnered as much critical acclaim as their contemporaries in the Rolling Stones, their commercial success could not be denied. With the release of their sprawling double-LP ‘Physical Graffiti’ just around the corner, the time was ripe for Zeppelin to take things up a notch with a truly massive tour of North America.

In something of a break from the past, the group was determined this time around to turn their concerts into a grand spectacle. Whereas before the music demanded all of the attention, Zeppelin commissioned an elaborate light show replete with lasers to add a stunning visual component. In an even more jarring turn, they'd also invited a cadre of national media reporters to follow their movements and lob a few questions their way in the down hours, the goal being to rehabilitate their image as debauched marauding barbarians.

The 38-date tour formally kicked off on Jan. 18 at the Metropolitan Sports Center in Bloomington, MN. Things didn’t exactly get off to the best start. Just before the leaving for the States, Jimmy Page broke his left ring finger when it got caught in a train door, leaving him without the use of the crucial digit. The first show, while much shorter than many anticipated, was well-received, but shortly thereafter disaster struck when Robert Plant came down with a savage flu. As soon as the singer began to shake off the effects of his illness, John Bonham was hit with a stomach problem.

The band soldiered on and managed to get through that first month or so of the tour, albeit with a string of less-than-stellar performances to their name. By the time March came around however, things clicked in. Plant and Bonham were healthy once again, and Page was finally able to utilize the full force of his left hand. Many consider the band’s collection of shows on the West Coast of this tour, especially up north in Vancouver and Seattle, to be amongst the best they ever played.

They wrapped up the North American leg on March 27 at the Forum in Inglewood, CA, at which time Plant wistfully discussed the tumultuous two-and-a-half months to Cameron Crowe in Rolling Stone. “Looking back on it, this tour’s been a flash," he said. “Really fast. Very poetic, too. Lots of battles and conquests, backdropped by the din of the hordes. Aside from that fact that it’s been our most successful tour on every level. I just found myself having a great time all the way through.”

Afterwards, the band had their entire tour set-up shipped to London for an iconic five-night stand at Earl’s Court. Once those gigs had finished, the plan was to head back to America for a second leg. Unfortunately, Plant was seriously injured in a car accident on the Greek island of Rhodes which put to bed any thoughts of more touring. It would be another two years in fact until the band took the stage together for a full show.

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