What is the one pop song that says to you: "1970's"?

I’m listening to a Live365 station that streams 60’s and 70’s music. There’s been a bunch of old favorites playing tonight: Moody Blues, Badfinger, Pink Floyd, BTO, Kosmic Blues, among other greats. The song for me that sums up the 70’s and high school is, Rambling Man. I know for some of you this is, like, present day, but for me it was 35 years ago: walking around campus, hearing the piped in music (with the station playing obviously voted in by popular vote – and not yet restricted by DMR or any other patent restrictions – bah!). This and Fleetwood Mac’s Rhiannon

What’s your favorite 70’s tune?