China is protect and isolated from the rest of the world. All sides of China are protected.
North and Northwest: The Gobi Desert.

The Gobi Desert is not like the Sahara Desert in the way that it is just miles and miles of sand dunes and heat. Rather, the Gobi Desert is a very large barren area that little can thrive in.

Southwest: The Himalayas

This is the largest mountain range in the world. There are very few passes to get from China to the western part of Asia. China and India are next door neighbors and did not have a relationship for hundreds of years because of the size of this mountain chain.

East: Pacific Ocean

No one had the technology to sail and attack the Chinese shore. The Ocean was much too big and there was no one out there able to attack. Defending the East was not a problem until the Ming Dynasty which is the 11th and 12th century AD. The Chinese Dynasties started around 2000 BC. That is nearly 3000 years without a problem.

Southeast: Jungle

The jungles of Southeast Asia are some of the dangerous in the world. The vegetation, climate, animal life, and size of the jungles make travel difficult for small caravans, let alone armies to cross.

Chinese rivers are much like the rivers found in Mesopotamia. They are wild and can destroy without a rhyme or a reason.
The Huang River (Yellow River) flows for nearly 3,000 miles. It is called the yellow river because of the yellow color that silt and dirt of the area that flows into the river.

The Yangtze River in central China flows for nearly 4,000 miles. It is only behind the Amazon River of South America and the Nile River in Egypt in length. The Yangtze River makes rich valleys for crops and helps many cities in China, but it still possesses' a very violent side.