Like 'Free Bird' or 'Iron Man' or 'You Really Got Me,' Led Zeppelin's riff-tastic anthem 'Stairway to Heaven,' No. 3 on our countdown of the Top 50 Led Zeppelin Songs, is so ingrained in the DNA of rock music that, ironically, it's often overlooked. We've heard these songs so many times in so many formats for so many years, they've become cliches and punchlines -- the kind of song you yell out for during a crappy band's encore when you're trying to snag a cheap laugh. 'Stairway to Heaven' isn't just a great rock song; it's the great rock song -- it can't be over-played if it deserves to be.

The centerpiece of Zeppelin's 1971 untitled fourth album, ('Zoso' or 'Led Zeppelin IV,' depending on who you ask), 'Stairway' set the blueprint for all multi-suite hard-rock epics to follow, though none have come even remotely close to matching its greatness. Even on the 12,000th listen, the track's ethereal magic never wears thin, and that timeless build from Jimmy Page's shimmering, fingerpicked guitar intro to the riff-driven full-band attack is one of the most visceral moments in the history of recorded music.

Though Zeppelin were never truly classified as a 'prog-rock' band, 'Stairway' is without a doubt the band's most 'progressive' and technically challenging (John Bonham reportedly struggled with the timing in the early stages of recording, fumbling through the track's many movements), also showcasing Page at his most ambitious as an arranger.

'Stairway' crystallized the essence of the band,' Page stated to Guitar World in 2008. 'It had everything there, and showed the band at its best.'