*4.3. The Parent City of Chongqing in Experience and Perception*

In the aforementioned study, historical maps and documents are used as primary sources to examine the historical change process of the visible portion of the historic urban landscape utilizing tools and techniques such as the spatial syntax approach, ArcGIS, and the historical map translation method. The historic urban landscape also has a perceptible component, which is often the intangible component and includes urban activities, folk traditions, and local culture. The written and visual works that document the city's evolving face may shed light on the metropolis from a new angle. Chongqing's river and boats, as well as the city's meandering alleyways and alleys, are chosen in this paper as representative cultural aspects of the river and mountain city [61].

Chongqing's expansion and development coincided with the city's location between two rivers; water transport was crucial to the city's growth and prosperity throughout the Republican period (Figure 12). It used to be that ships coming up the Yangtze from the lower sections of the river would moor on the other bank of the city, necessitating the use of ferries to travel to the city itself. Chongqing's river, docks, and boats are cultural icons that should be preserved as part of ongoing attempts to revitalize the city's historic core.

**Figure 12.** (**a**) Sketch of looking north of the river from Jialing wharf in the early-modern times; (**b**)Dongshui Gate in the 1920s; (**c**) Sedan chairs in Chongqing; (**d**) Stairways of Chongqing in the 1940s. (Source: Sketch by Paul Hogarth, photograph by Sidney David Gamble, William.l.Dibble and H.Allen.larsen, Life magazine).

Chongqing is built on a hilly, undulating landscape; therefore, the city's winding, tiny mountain streets, and alleys, as well as the stairways linking various heights, are distinctive characteristics. Since ancient times, the mountain city's twisting alleys and lanes have not only provided a means of transportation but have also served to interpret the personality and qualities of the area. Chongqing's unique hilly environment necessitated the adaptation of a unique mode of transportation: the sedan chair (Figure 12). Sedan chairs were often seen on the city's stone stairways. Many old streets and alleys remain today, preserving the city's unique memories from before the 1980s when urban construction was hurried forward, and the low modern hammock houses were replaced by modern high-rise houses, and after the liberation when houses could no longer be renovated due to technical and economic constraints. Urban reconstruction efforts should not destroy or drastically alter the look of ancient streets and alleyways.

#### **5. Conclusions and Prospects**

In the past 40 years, a standardized construction mode has been universally adopted in Chinese historic urban areas as the most efficient urban planning strategy [62]. Urban regeneration is a comprehensive and integrated practice [63], and historical and traditional spaces must be adapted to modern needs, preserving historical character and regenerating these areas for adaptation to the changes ahead [64]. The tension between modern society and traditional space in China is apparent, as well as traditional to modern. The urban form bears the marks of the transition from rural to urban [65]. Urban change gradually threatens the historic areas of the city [66], and urban heritage preservation depends on the understanding of the historical evolution.

According to the methodology and framework of urban morphology, several researchers have studied the morphological changes in Guangzhou and come to the following

conclusions: the city has become denser and more functionally diverse internally [57]; the morphological units show a general characteristic of inheritance and succession; the overall structure of street space is more stable throughout the process [39], and the evolution of urban spatial form is closely related to local political, economic and cultural factors [67].

The most intuitive outcome of this research is the creation of a historical map of Chongqing using a modern map as the base map. This historical map contains information on various stages of the city's history, features the overlapping of information from multiple periods, and allows for easy comparison. Three distinct eras of contemporary Chongqing's parent city are shown in Figure 13, each with its distinct street layout and network of public transit lines, illustrating the city's sequential and evolutionary development (Figure 13). After laying the groundwork with qualitative research, the next step is to integrate quantitative methods with technological tools to compute the development of geometric, structural, and functional factors and present the results in a scientifically rigorous manner. For all other cities, this work has some ramifications.

**Figure 13.** (**a**) The transportation network in three distinct eras; (**b**) The public transportation network and station in three distinct eras. (Source: Historical maps, Chongqingshizhi, Google Earth and etc.).

The contributions and innovations of this paper: firstly, the integration of a universally suitable framework and methodology based on the use of HUL and urban morphology frameworks in conjunction with the actual situation in China. Using the parent city of Chongqing as a case to develop the interpretation, dividing the urban historical landscape into a visible part and a perceptible part, the visible part being the part based on urban morphology, exploring the planar pattern and spatial form. The perceptible part combines social activities, urban imagery, and daily life [68]. Secondly, the historical materials are analyzed by GIS and Depthmap technical tools, combining qualitative and quantitative research methods to provide new ideas for the empirical study of space. Thirdly, the study presents a technique for the investigation of spatial change in mountainous cities through the use of historical maps as a source and the spatial shaping traits of three-dimensional mountainous cities.

The study has certain limitations. The scale and precision of the research are somewhat lacking due to the absence of historical data that have prohibited the restoration of the early urban building fabric, for example, in the Guangzhou Urban Study [57], and the discussion is mainly focused on the plan, and there is a lack of discussion on land use and function. These could be used as guidelines for future research, on the one hand, to dig deeper into the historical materials and, with the help of sophisticated tools, perhaps archaeological methods, to deduce more accurate historical maps of the city, and, on the other hand, to carry out research on the internal characteristics of urban spatial form, such as function and

land use, and to consider public participation, government policies and other aspects [69], to improve and revise the existing framework and methods.

In China, large-scale demolition and construction have been common and standard in the past 40 years, and some practices have demolished the heritage and reconstructed the imitation in historic urban areas, such as "Antique Streets" or "European Streets" [62]. Some projects constructed many odd-shaped buildings and broke the historical relationship among the historic landscape [70]. These practices failed to balance conservation and development due to a lack of understanding about historic preservation.

The findings of this study may be used to preserve historic areas and serve as guides or strategies for urban planning and regeneration. Firstly, it can be used as a foundation for cultural heritage conservation, as cities with historical heritage have an advantage in the global market [71]; the findings of this study can be used to determine a location's historical spatial pattern and preserve the original pattern as much as possible [72]. The findings of this study also offer a foundation and a plan for urban planning and urban administration from the perspective of the historic urban landscape.

According to this study, some urban planning strategies can be suggested. To ensure the sustainability of the planning process, the planning horizon can be divided into three levels: point, line, and surface. At the point level, which refers to buildings and plots (Figure 1), the historical and memorial buildings should be preserved entirely [73], such as the monument to the People's Liberation, the Chongqing people's auditorium, and other landmarks. Some larger historic buildings, such as the Luohan Temple, Qing Dynasty Ba County Government Offices, and people's park, should be preserved and given new uses [73] for attractions, leisure, and other function to ensure the rebirth of historical heritage [74]. At the line level, referring to streets and street-system (Figure 1), main historic roads and rivers should be focused on, linking historic buildings and integrating them into some lined landscape that included parks and was able to accommodate a range of activities to help citizens integrate and accept the new roles [74]. For instance, Chongqing's two rivers and the wharf space have long served as a symbol of the city's collective memory, and consider reactivating the ferry routes and holding regular festivals. Moreover, the south main road, which linked Chaotianmen Wharf, Huguang guild hall, People's Park, Dongshui Gate, Nanji Gate, and other historic buildings (Figure 7a), was lined with shops of all kinds, gathering merchants from all over the world, and was also the seat of the early government in the 1920s. It should be highlighted for its historical character through regular closure of the road during important festivals to hold large fairs and trading events. At the surface level, referring to historic blocks, Chongqing's parent city could be divided into some different blocks, such as the Chaotian Gate block, Jiefangbei block, Nanji Gate block, etc.; each of them has different historical memory and characters, which should be considered as the main feature of the block. Such as the Chuqi Gate block, in ancient times, there was a folk rhyme that "Chuqi Gate, the herb house, cures all kinds of diseases", and it was still the most important market for Chinese herbal medicine since the 1920s, with many of the country's most famous old pharmacies having warehouses and shops here. In this block, Chinese herbal medicine culture could be highlighted by transforming some historic buildings into Chinese medicine halls and Chinese medicine markets. Moreover, during the regeneration process, based on the city history map from this research, the relationship between property rights, space, and resident behavior to understand the evolution of Chinese urban historic areas and internal motivation.

**Author Contributions:** Conceptualization, D.S. and S.D.; methodology, D.S.; software, D.S.; validation, D.S. and S.D.; formal analysis, D.S.; investigation, D.S.; resources, D.S.; data curation, D.S.; writing—original draft preparation, D.S.; writing—review and editing, D.S.; visualization, D.S.; supervision, S.D.; project administration, D.S.; funding acquisition, D.S. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.
