Led Zeppelin - Physical Graffiti
Widely considered the last great Zeppelin album, Physical Graffiti marked the band's best attempt at experimentation. And although it doesn't have as many classic Zeppelin hits among its massive 15 tracks, it makes for some of the bands most interesting work. Tracks like "Kashmir" and "Trampled Under Foot" are unexpected deviations that the band pulled off in an incredible way.
Beyond that, Physical Graffiti is a treasure chest of Zeppelin deep cuts, with a half dozen great tracks like "Ten Years Gone" that haven't become over-played over the last four decades. There's even the weirdo charm of "Boogie with Stu" that features Ian Stewart from the Rolling Stones, and somehow works on this album.