Historical cityscapes have changed because they were the expression of the dynamic interaction between natural and cultural forces in geographical condition. Geography was the most stable, inheritable and lasting forces for its founding and development. Therefore, usually the planning of cityscapes is only limited in the architectural space, from individual buildings, streets and blocks to whole city. My research is from the viewpoint of geography system to study the historical changes of the cityscape. Nanjing, a city located along the Yangtze River, originated 2500 years ago where ten dynasties established their capitals. Nanjing's geographical condition is characterized by three ranges of low mountains and hills, two branch rivers and three lakes. A well known praised name for ancient Nanjing: Zhong Shan Mountain was as a dragon prone and Stone City was as a tiger crouch. From its boring time to the last dynasty the planning ideas of Nanjing's landscape was in the line with the system of its mountains and hills, lakes and rivers. However, modern Nanjing has been departing farther from the background of the harmonious development of city and nature for contemporary construction. The mountain ranges with the historically gathered "imperial spirit of Capital" has been fatally ruined and dissected. My research focuses on the following ideas: an analysis of the characteristics of systems of the mountains and rivers in the historical periods, and an investigation of sites of historical sites along with the system, in order to search for the laws of historical evolutions and spatial structure changes of cultural landscape in geographical system. Further research is needed to get a better understanding of the key core and the landmark in historical geographical condition which once played an important role in its origin and development process. Thus distinguishing and preserving the sites is important for keeping the characteristics of the cityscape, conserving the natural continuous characteristics of mountain ranges and rivers, identifying geographical system to composite the mountains, rivers, urban park zones, avenues and Ming Dynasty wall into a whole landscape system, and extending the traditional preservation planning and cityscapes planning to that of geographical landscape system.