The Thistle & Shamrock: The Carrying Stream

It once took centuries for a ballad like "Barbara Allen" to work its way through the British Isles and across the Atlantic. Now, music flows freely back and forth as artists on both sides of the ocean explore and fuse flavors from Celtic, Appalachian and old-time music.

This week, hear from musicians who exemplify this exchange, including Dolly Parton, John Doyle, Jean Ritchie and Anaïs Mitchell.

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