The best reissues, box sets and archival recordings released in 2021 include a mix of live tracks, session outtakes, alternate versions and long-forgotten songs pulled from the vaults and dusted off.

And while you'd think by now - decades after CDs gave the music industry new life with box sets and other expanded collections - the shelf-clearing wouldn't yield much of interest, let alone essential albums, that's not the case at all, as the below list of Top 15 Reissues of 2021 proves.

Whether it's deep dives into specific eras of the Beach Boys', Bob Dylan's and Joni Mitchell's careers, or revisions of classic albums by the Beatles and a classic solo record that came out soon after their breakup, the sets below outline distinct periods rather than discography overviews.

A couple of live shows from the archives of Bruce Springsteen and Neil Young also appear, chronicling the artists during peak, and somewhat significant, years of their long careers. On the same path, two different Black Sabbath boxes - celebrating a pair of albums made by the original, classic lineup - include concert recordings that have as much to do with the years in question as the studio output.

But if there's an overall takeaway from the Top 15 Reissues of 2021 it's that the archival closets are far from bare or even close to exhausting their supplies. Most of the albums on the list are essential companion pieces to classic records and deserving additions to their respective artists' catalogs.

Top 15 Reissues of 2021

The year's best archival releases include deluxe box sets, expanded anniversary editions and long-lost recordings from the vault.

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