Private pilot (sadly grounded for quite a while now). Frequent flyer (United 1K). Space flight advocate and fan. Afraid of open heights.
Afraid of open heights?!? Well, not exactly afraid, but looking down the atrium of the Shanghai Hyatt from the 85th floor to the lobby on the 56th did give me a sort of dizzy feeling, even though the railing was quite solid and chest high (so not really an "open height" in any literal sense). It's an amazing sight, as is the night view from the 86th floor restaurant. Shanghai is one visually stunning city.
Now I'm in Beijing and will visit the Great Wall tomorrow. Let's get a space connection in here, one I vaguely recall discussing somewhere before, maybe in this blog. Is the Great Wall the only man-made object visible with the naked eye from space as is sometimes claimed? Depends on where you are in space. From LEO (that's low earth orbit, Shuttle altitude), many man-made objects such as highways, ships, railroads, etc. can be seen depending on conditions, often including the Great Wall. From the Moon? This was claimed somewhere too, but beyond a few thousand kilometers, no man-made features are visible on Earth, and from the Moon, just patches of white, blue, brown, yellow, and sometimes green.