Regeneration of Zhuangyuanfang in Guangzhou Historic District Based on Careful Urban Renewal

China's urban development has started to shift from rough growth to refined renewal of old cities, and exploring the renewal mode of old cities has become an important topic of urban development nowadays. The renewal of old cities is of great significance to the development of cities, as they are important carriers of the collective memory of cities, and their renewal has important economic, social, and cultural significance. Guangzhou has also experienced many explorations of old city models, from "three old renovation" to "micro-renovation", and has been exploring the problem of the old city's inventory of buildings, namely the contradiction between the decay of the old city's physical environment and the current demand. And the old city of Guangzhou is also facing the problem of transformation of the historical district. In this context, this paper studies the old city renewal model of "Careful Urban Renewal" in Germany after the same major demolition and construction, and explores a " cautious" model applicable to the old city renewal of Guangzhou. First, this article analyzes and summarizes the development process of Careful Urban Renewal, analyzes the concept of Careful Urban Renewal from the period of demolition and construction to the new period of Careful Urban Renewal after the reunification of Germany, and compares it with the model of micro-renewal in terms of policy, funding source, organizational structure, public participation, and operation process, and analyzes the dilemma of domestic micro-renewal in terms of renewal mechanism, organizational structure, and public participation, as well as the implications of Careful Renewal in terms of renewal mechanisms. Secondly, the article analyzes the Kreuzberg and Spandauer Vorstadt areas that applied the concept of Careful Urban Renewal during the IBA period and after the reunification, and summarizes the spatial strategies from planning concepts to urban design through three levels: neighborhoods, buildings, and urban spatial catalysts. Further, the article analyzes the problems of Guangzhou's old city regeneration through the summary of Guangzhou's old city development and two typical regeneration cases, analyzes the direction of Careful Urban Renewal for Guangzhou's old city regeneration, and formulates the strategy of Guangzhou's old city regeneration. Finally, a typical historical district of Zhuangyuanfang in Guangzhou's old city is analyzed to verify the applicability of Guangzhou's old renewal strategy. Through the analysis of the current situation of the historic district of Zhuangyuanfang, it is concluded that there are problems such as the lack of public space, old infrastructure, and the lack of compatibility between the architectural style and the historic district in terms of physical space; there is a loss of historical characteristics in the human environment and the lack of positive interaction between the industry and the district. Based on the current problems, a "cautious" regeneration path is formulated for the historic district of Zhuangyuanfang: Clarify the role of funding policy, funding, and NGO organizational structure in each phase of renewal; cautious regeneration of public space; guidance for the regeneration of the existing of buildings; cultural catalysts in the neighborhood space; and lead public participation in the whole stage.