The song "Stairway to Heaven" by Led Zeppelin is in the key of A minor. A Minor (which is the key of C but based around a tonal center of A), so A B C D E F G A, or all the white keys on the piano. You might also see it described as being in A Aeolian, which means the same thing.
Song Metrics\n\n The track runs 3 minutes and 5 seconds long with a G key and a major mode. It has low energy and is not very danceable with a time signature of 5 beats per bar.