As you'll see in the following list, Bob Dylan's many studio and live albums tell only part of his story. Scattered throughout his 50-plus years as a recording artist are hundreds, if not thousands, of discarded songs and ideas. Some became other songs, some were reworked into familiar tracks, and others were just left on the shelves.

The Bootleg Series, which launched in 1991 with a three-disc box set that included tons of previously unreleased songs from throughout Dylan's long career, fills in some of those pieces. Over nearly a dozen volumes and almost a quarter century, Bob Dylan's Bootleg Series has given such fabled recordings as the Royal Albert Hall concert, the Basement Tapes and various leftovers from his classic mid-'60s trilogy of albums (including Bringing It All Back Home, Highway 61 Revisited and Blonde on Blonde) their long-hoped-for official releases.

The series has even shed an entirely new light on at least one scorned LP (1970's Self Portrait, one of rock's most reviled records) and put a divisive mid-'70s tour into perspective, as well as sharpened the dreaded born-again years. But most of all, the series – which now includes more than a dozen volumes – has unlocked a treasure chest of rare gems by one of rock's greatest artists.

We've ranked the albums in Bob Dylan's Bootleg Series from worst to best, but all of them are required listening for anyone interested in piecing together the history of this enigmatic and legendary singer-songwriter.

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