久住金陵的人，都知道南京有一大一小两条江，大江是长江，小江是淮水，即今秦淮河水系。自古以来，秦淮河就是长江下游的一条重要河流，它分派屈曲，不类人工，全长不过100余公里。其东北面是宁镇山脉，东面是茅山山脉，西南面则是描川天白山、相堂、牛首和吉山等．西北?.. People who lived in Jinling for a long time knew that there were two big and one small rivers in Nanjing. The major rivers were the Yangtze River and the Xiaojiang River was the Huai River. Now the Qinhuai River system. Since ancient times, the Qinhuai River is an important river in the lower reaches of the Yangtze River. It distributes buckles and does not require artificial work, but the total length is only 100 kilometers. The northeast is the Ningzhen Mountains, the Maoshan mountains to the east, the southwest is the Tianchuan Tianchuan, Zhaitang, Niuzhu and Jishan. northwest?..