Architecture:
The Great wall is the largest wall in the world , it was build over 2000 years ago by Qin Shi Huangi and now its called Wan- Li Quang- Qeng.The Great wall is the building project with the longest donation and greatest cost in human lives. Also during the Ming Dynasty 1368-1644 the Great wall was enraged to 6,400 kilometers.
Most people couldn't afford to live in fancy houses so they lived in small houses made of mud brick with one room and a dirt floor just like most people in Roman Empire or West Asia.But the rich people had fancier houses and would built fancy temples and palaces but they had to built them by strict rules of designing Chinese buildings follow the ideas of Taoism or the other Chinese philosophers.
Invention:
During medieval china scientists seem to have been interested mainly in engineering and practical inventions. About 450 B.C. during the warring states period Chinese black smiths invented the crossbow. 100 B.C. to 100 A.D that paper was first invented and compass for telling North from South.