First step : Stopover in Beijing
Before joining Korea I first had to make stopover in Beijing during 20 hours. I understood that 20 hours was a very long time. So I took an hotel room directly into the airport (you pay on a per hour) to be able to take a shower, get some rest and be able to ask my luggage the time that I visited some of the city. The room was small but adequate, however it was a very poorly maintained collective shower (odors, dirt). But the good point : It was not very expensive of course.
On the plane I met a girl who had spent a week there and who advised me to visit the "Forbidden City" and Tian'Anmen Square. With the Olympics, the airport serves very well the city thanks to a kind of large and modern subway line "ABC".
Then I took a taxi. This is where the problems started. Taxi drivers does not speak a word of English and they do not seem to understand my Chinese accent when I tried to pronounce the name of my destination. This was a total misunderstanding. After four failed attempts, I finally found a seller in a watch shop that could write me the name of my destination in Chinese on a piece of paper.
Regarding the visit in itself, I was rather disappointed. The "famous" place is actually a huge place but completely empty and uninteresting. In terms of the Forbidden City, very stately and impressive from the outside, it turns out because that day it was closed to visitors. No luck. Moreover I found the Chinese very closed : As a foreigner they would not told me or helped me most of the time.
To conclude, I know that 20 hours it is really too short to discover a city and a country so rich culturally speaking but I stay however on a bad feeling of disappointment as regards Beijing.