Often referred to as Led Zeppelin IV, this 1971 album is one of the most iconic rock records ever made. Featuring classics like "Stairway to Heaven," "Black Dog," and "Rock and Roll," the album blends hard rock with folk and blues influences. The band's virtuosic performances and innovative production techniques have made this album a cornerstone of rock music. Its enduring popularity and influence are a testament to Led Zeppelin's monumental impact on the genre.