The joke writes itself: "How do you know when a prog tune ends?" "When it's time to flip the record over."
In all seriousness, picking the best progressive rock tracks can be tricky on a practical level — projects like Tubular Bells and Thick as a Brick blurred the line between "song" and "album" in the first place. And other pieces, like Genesis epic "Supper's Ready," are so expansive that it feels weird comparing them to four-minute singles. Then there's the issue of genre: Can a non-prog band moonlight with a song or two? And should pop-friendly moments from canonical prog bands be on the table? Ah!
Decisions, decisions — but, ultimately, fun ones. If Yes can solve the creative puzzle that birthed "Close to the Edge," we can suck it up and put this list together — even if we lose a little sleep in the process. What other musical style could spark such nerdy debate and deep thinking?