Why is Nanjing called the dragon plate of the tiger?

Nanjing is located at the intersection of the Yangtze River, the east-west water transport artery, and beijing-shanghai railway, the north-south land transport artery, and is known as the "southeast gateway, the north-south throat". The Shanxi section of Ningzhen lies across Nanjing. If Zhongshan in the east of the city is long and tortuous, and the rocky mountain in the west is like a tiger, there is a saying that "Zhongshan is long and tortuous, and Shicheng is surrounded by tigers". The Yangtze River flows from west to south, and then turns to the east. Qinhuai River and Jinchuan River meander in the city; Xuanwu Lake and Mochou Lake are hidden between the east and west mountains and rivers, with magnificent momentum and beautiful scenery.