because mountains flanked there north and west jungle flanked there south and water there east

Well, didn't we learn that in our syllabus?
It was because China was surrounded by natural barriers.
In the north, there was the Gobi Desert.
In the south, there were thick forests.
In the west, the Himalayas.
And in the east, the Pacific Ocean.
All these limited china's contact with other early civilisations. As a result, the chinese thought they were the only civilisaed people on earth. Their only contact was with some wondering tribes from Manchuria and Mongolia. The chinese considered all outsiders to be barbarians. Also, they believed that they were at the centre of the world, they called their kingdom the 'Middle Kingdom' (or "zhonggup")

Thanks a lot. You got me ready for the exams.

OK thanks

Ok thanks

It isolated and protected by great wall in North desert and mountain in West and pacific ocean east Himalayas in south

Thanks

In the old days when people rode horses, every country was isolated from every other country. You could ask why Singapore was also isolated from the rest of the word. Or India, or the African countries, or Australia, or Europe...it's the same for everybody and every country.

* rest of the world

Whilst it is true that Ancient times were pre-globalisation and hence every where was isolated to a degree, Ancient China was significantly more isolated than Europe. Due to the physical geography of Europe being less isolating among different countries, there is a long history of cross-regional commerce and exchange of philosophical in Ancient Europe which is not true of Ancient China.