This is a topic I thought would be interesting for people to sound off on, and although I understand it to be mostly subjective, I think there are some definite criteria you can look at. For this post, I'm just considering Classic Rock, pretty much the late 60's thru the 70's (for example, I don't consider U2 to be classic, because most of their stuff has come in the 80's and 90's). I also looked for songs that can be seen as groundbreaking or defining. I'm posting my top 5, in alphabetical order, let the arguing begin.
- American Pie, Don McLean 1971
This is the song with the chorus everyone knows, but seemingly not many have listened to it all the way through. This stroy song of epic length (over 7 minutes) is packed with symbolis

m that garners several different interpretations. Most common and practical is the view that McLean wrote this song as a tribute to early rock & roll pioneer Buddy Holly, who was killed in a plane crash. The song is also a history lesson and commentary on Rock and McLean's life up to that point. It touches on Dylan, the Beatles, the Stones, and refers to social events of the time. This, plus its sing-along-ability and superb songwriting make it an obvious choice for this list.
- Baba O'Riley, The Who 1971
Another great song out of '71 is one of my personal favorites (obviously). Coming off the W

ho's classic album
Who's Next, it showcases the band's pineering use of the synthesizer coupled with Pete's power chords and an unforgettable piano riff. This convey's to the listener the realization of the "teenage wasteland" the artist finds himself in, but with flare only the Who can provide.
- A Day in the Life, The Beatles 1967
Have you heard of these guys? Hard to pick one song of their's, but this can truly be seen a

s epic. They masterfully syntesize two different songs here, and provide a great background of experimental studio music. The separate parts one by Lennon and the other by McCartney show the stereotypical difference between the two writers. While John begins musingly and dark, Paul comes in with a whimsical verse, which slips back into the original tone of the song. It all comes crashing together in one magnificent chord followed by some weird studio editing stuff. Some will think the Beatles music isn't as good as the people they influenced, but in the case of this song, the Beatles are the masters.
- Dream On, Aerosmith 1973

Of all the songs on this list, this is the one I have listened to the least, but I still consider it a very solid choice. Containing incredible riffs, solos, and vocal performance, this ground-breaking power balled is the epitomy of a rock song that leaves the listener wanting nothing but to hear it again. What's really impressive is that thhis song appears on their debut album.
- Hotel California, The Eagles 1976
Like all of these songs, this is the complete package of awesome music and great songwr

iting. The Hotel California is a commentary on the temptations and dangers the Eagles see in the wild lifestyle rock offers. This insightful lyric is backed by incredible guitar solos, which leads to the issue of which version is better, the album or live take. Both are great, as the original is pure and fresh while the live one offers multilayered insturments to bring the song to life.