Why did Sun Quan move the capital to Jianye?

I think it may be because of ancient geomantic omen. Jianye has a good geographical context and developed well by the natural barrier of the Yangtze River. It is difficult for Wei to attack across the river. Wu has heavy troops in the local area and natural hazards in the Yangtze River, so the capital Jianye is still very safe.

Zhang Hong (151—211year) was born in Guangling. Soochow counselor, together with Zhang Zhao, is called "Two Zhang". He suggested that Sun Quan move the capital to Moling (later renamed Jianye). Zhang Hong died at the age of 60. Sun Quan wept for it.

It is reported that Zhang Hong, who has a long history, resigned and went home due to illness. Now that he is dead, there is also a memorial book. In the book, Sun Quan was advised to move to Moling, saying that the mountains and rivers in Moling have the spirit of emperors and can be moved here as soon as possible, thinking that this will be an eternal industry. When Sun Quan finished reading, he cried, "Zhang Zigang advised me to go to Moling. Why didn't I follow? " That is, I ordered the capital to move to Jianye and build a stone city.