Doors in Beijing
One of the striking differences in everyday life of Beijing is what they use instead of doors now, when temperatures are far below zero.
I noticed two types of these ad hoc doors:
1) Thick heavy blankets made of rough cloth, with a window. Looks very barbaric and unaesthetic, but you'd be surprised at the number of places where you can see this - from entrances to public toilets and tiny shops to huge "European" supermarkets like Carrefour.
2) Transparent plastic curtains, sometimes so yellow and worn out that you cannot see through them. This type is used everywhere, too, from small shops to modern multi-storey malls.
Sometimes I come across a mixture of these two types, such as at the entrance to Tiananmen West subway station - see the photo on the left.
Why not install regular doors? The answer, I guess, is that the cold time in Beijing lasts for only a couple of months, and these improvised doors are removed later, while regular doors would only add problems in the warm time.