Looking at the photo on Tinpis post brings me back memories.
In 2002 i spent 10 days in GuangZhou which is the largest city in the Canton province in south China about 300km inland from HK. The entire time i have not seen the sun, visibility would have been about 200 meters every day. The other thing i have not seen: BIRDS. You know the living kind with feathers... May be because the military airspace does not allow them to fly or they cannot afford their IFR renewals
(There was no shortage on the menu at restaurants though)
Needless to say i could not wait to get out of the place!