Generally speaking, people think that Nanjing is not suitable to be the capital, and those who have been the capital in Nanjing are short-lived dynasties. Beijing's geographical location is conducive to maritime transportation, and it can rely on the Bohai Bay for coastal defense, which is an important support for both economy and military. Nanjing does not have these geographical advantages. At the same time, Beijing is the center of power left over from the Qing Dynasty. This is also determined by history. It is easier to promote culture by establishing a capital here. To give a simple example, such as Mandarin, Beijing and even the north have natural conveniences.
In addition, where the capital of a country is is not necessarily determined by its glorious history. Many countries' historical cities and even the largest cities are not capitals. For example, in countries such as the United States and Australia, the location of the capital may be affected by multiple factors. After all, history has passed, and Nanjing's previous glory may not be comparable to Xi'an. So this is not the main reason for deciding where the capital of our country is.
Nanjing is close to water sources and has convenient transportation. However, when the new China was established as the capital, Nanjing was the first to be eliminated. The Republic of China had just ended, and the new regime chose the capital. It is not difficult to understand the difference. Judging from ancient China, those with capitals in the north were able to unify the country. This was true for the Qin Dynasty, Han Dynasty, Jin Dynasty, Tang Dynasty, Yuan, Ming and Qing Dynasties. The Three Kingdoms, the Five Dynasties and Ten Kingdoms, and the Song and Jin Dynasties were all periods of relatively balanced power, and there was no question of unification. Moreover, during the founding of the People's Republic of China, enemy planes bombed Shanghai and established their capital in Nanjing. This was not a safe location.
At the end of 1949, the Kuomintang army still had more than 600,000 troops. Once the enemy forced a landing, there would be no danger to defend the vicinity of Nanjing, and it was very likely that they would have to retreat temporarily. In 1937, when the Japanese army came from Shanghai, the Chinese army retreated all the way to Sichuan, and Jiangsu and Hubei were completely lost. Therefore, once the capital is established, it cannot be easily moved, and the location needs to be carefully considered. In the same way, Nanjing is not only not the capital, it is not even a municipality directly under the Central Government. There is a more developed big city Shanghai nearby.
Beijing was chosen in 1949 partly because Beijing was the capital of the Yuan, Ming and Qing dynasties, forming a core atmosphere. Beijing is surrounded by mountains on three sides, and the mountains form an embrace, which is very good from a Feng Shui perspective. It happens to be the choke point from Northeast China to North China, with convenient transportation and distinct four seasons. Moreover, Beijing was peacefully liberated in early 1949 and is very well preserved. Another point is that Beijing was closer to the then Soviet Union and connected by railway. Once Beijing is threatened, it can retreat to the northeast to the north and to Xi'an to the west. In this comparison, the conditions are more suitable than those in Nanjing.
Extended information
Nanjing belongs to the hilly area of ??Ningzhen, which is dominated by low mountains and gentle hills. Low mountains account for 3.5% of the total land area, hills account for 4.3%, and hills account for 53%. %, and plains, depressions, rivers and lakes account for 39.2%.
The Ningzhen Mountains and the Laoshan Mountains in the north of the Yangtze River run across the central part of the city, and in the south are the Hengshan Mountains and Donglu Mountains at the southern boundary of the hilly hills of the Qinhuai River Basin. Nanjing's plane position is long from north to south and narrow from east to west, forming a true north-south direction; the straight-line distance from north to south is 150 kilometers, the center is 50 to 70 kilometers wide from east to west, and the north and south ends are about 30 kilometers wide from east to west. To the south is a landform complex composed of terrain units such as low mountains, hills, valley plains, lakeside plains and riverside areas.
Baidu Encyclopedia-Nanjing