The weird thing about a band like Zeppelin is that, if you’re first discovering them while exploring classic rock for the first time as well, all of their bigger songs are, naturally, part of the hook. But there’s a danger of over-exposure with a band like this. Stuff like “Whole Lotta Love” or “Black Dog” or — of course — “Stairway To Heaven” are so in the fabric of the narrative of rock music from the last forty to fifty years, so ubiquitous on classic rock radio or lists of the greatest rock songs ever or whatever, that they can be the sort of material it’s impossible to hear freshly the first time you’re intentionally listening to them. Even if you’re a kid when you decide to listen to Zeppelin, chances are you’ve simply absorbed this stuff already, like “Smells Like Teen Spirit” or “With Or Without You” or “Hey Jude.” You can be robbed of that opportunity to be listening through Led Zeppelin’s second or fourth albums and be surprised by what comes next, just by virtue of some distant, tangential memory of having heard these songs a million times in the periphery.

What’s incredible about Physical Graffiti is that it exists almost entirely out of this. There’s a lot of well-known stuff on this album as well, but the only one that would probably qualify in that “Stairway To Heaven Ubiquity” category is “Kashmir,” and “Kashmir” still basically sounds insane relative to all those other super-famous Zeppelin songs. Any of Zeppelin’s first four albums are still pivotal, but so is Physical Graffiti, and in a different way. Today, it might be the most exhilarating Zeppelin listening experience because it’s lined with such superlative material that hasn’t been played to death on the radio for forty to forty-five years. It stands out from the early records because of that quality, and it stands out from Presence and In Through The Out Door, because while those records have a lot of lesser-explored Zeppelin material as well, most of it can’t touch this stuff.

In all its expansiveness, Physical Graffiti touches on just about everything Zeppelin ever did. It’s the big, mid-’70s panoramic one. Oddly enough, it’s one of those rare double albums where the sprawl feels earned and crucial and inextricable from the nature of the music, despite the fact that it wasn’t originally conceived as a double album. (Several of the songs date back to the third and fourth albums and Houses Of The Holy, and were resurrected for this.) Even though there’s plenty of hard rock songs here, Physical Graffiti has always struck me as the sustained image of Zeppelin at their most ethereal. There’s always been some quality here that has made me feel like Physical Graffiti was Zeppelin’s night album, a mysterious and twisty listen that lunges between moods and sounds, with songs that can sound decadent and lusty (“Trampled Under Foot” being the leader here) near some of the band’s most spectral material (anything from “In The Light” to “Ten Years Gone” to “Kashmir”). Somehow, it all holds together perfectly, and it makes for one of the best documents of what this band was capable of.