Do you like progressive rock? Do you have enough patience to wait through a 30 minute song? Are you a baby boomer?
Welcome to this very thread — which is about progressive rock. You can talk about it, and the bands that play that specific genre like Pink Floyd, Yes, ELP and King Crimson. Maybe overlaps with classic rock, but if it does progressive rock, then it should probably be discussed here on grounds that the music has enough prog elements like strange time signatures and more commonly, very long music.
Progressive metal do count, too, as metal is a subgenre of rock — This page might help you out in finding more about progressive rock.