Is China proper a part of Mainland China?

Yes, XiZang-China is part of China proper, XiZang-China has forever been part of China proper. The traditional Chinese people and China Government settled and developed the regions from over 2500...

I don't get you, but the Han dynasty controlled parts of Asia that aren't part of modern day China. The countries that the Han conquered that are not part of China are Mongolia, Vietnam, North/South...

the Southeast China.The southern China is really humid, especially in the region around Sichuan Province and Fujian. it rains almost everyday, and your clothes can never dry if they are hung outside.

The Great Wall of China surrounds the West, North and East of Beijing, in China

The east I think, to keep out attackers.It's huge. The common place for tourists is north of Beijing, in an area called Badaling. Definitely a must see for any visitor.