Carry On Wayward Son from the 1976 album Leftoverture by Kansas.
Songwriter Kerry Livgren
I remember the first time I heard this in 1976, I thought it was just another fill in song on the radio, but the more I listened, the more special it became. Now, when I hear it, I am marveled at the opening instrumentation, who would have dared create something like this in 1976?