Check out the full performance of Robert Plant and Alison Krauss and an all-star line-up of legendary musicians on @BBCTheOneShow now here https://plantkrauss.lnk.to/BBCTheOneShow | Robert Plant

“The Battle of Evermore” is a folk duet sung by Robert Plant and Sandy Denny, included on Led Zeppelin’s untitled 1971 album, commonly known as Led Zeppelin IV. The song’s instrumentation features acoustic guitar and mandolin playing, while the lyrics allude to J. R. R. Tolkien’s fantasy novel The Lord of the Rings. Released 8 November 1971, Recorded at Headley Grange, Hampshire, England. Written by Jimmy Page And Robert Plant and produced by Jimmy Page. Happy Anniversary Led Zeppelin IV. #ledze

WATCH: "I'm still desperately switched on to the music that surrounds me," Led Zeppelin lead singer Robert Plant tells Jeffrey Brown. | PBS NewsHour