Beijing is the capital of the People’s Republic of China and one of the most populous cities in the world, with a total population of 21,150,000 as of 2013. From Shanghai, it is quite a distance by train, anywhere between 4-5 hours by fast train. Definitely a weekend trip that would require leaving Friday night and leave Sunday evening. There is plenty to see there and you definitely want to see the Great Wall, the Forbidden City and Tiananmen Square and Temple of Heavens, and that’s just a beginning. I have to warn you, during curtain times of the year, the pollution can be back for breathing, so you might want to do a little research before going or wear a masks.
I took my parent to Beijing a few years ago because my mother said that, every time she goes back to Canada, people asked her if she saw the Great Wall. They think it’s only a small distance from Shanghai, which it isn’t, and could believe when she told them she hadn’t. We only went for 3 or 4 days and we tried to see as much as we could but still didn’t see a lot. We did see Tiananmen Square, the Great Wall (even though once I got my parents on top of the wall and took a few photos, they were too tired to continue) and the Forbidden City. If you are planning to see the Wall, you will require to take a bus from Beijing, and most hotels can tell you where to go to get the tickets.