Was flying CA from PVG to HKG mid afternoon in October and had an incredible view of Seoul as we flew over at 30K+ feet. Even more spectacular was watching an air show (no not that air show) going on below with an aerobatic team doing their loops and bursts with coloured contrails marking the paths of their fighter jets! Unfortunately my camera was packed in the overhead and the person next to me in the aisle seat was sleeping so made getting it impossible.