Defense-Connectivity Synergy in the Spatial Evolution of China's Heritage Corridor Settlements: A Multidimensional Quantitative Study of the Guangou Section

Yun ZhaoLINGYU XU^*

• Beijing Jiaotong University, Beijing, China

Heritage corridors represent complex cultural landscapes shaped by the historical interplay between military defense and transportation connectivity. However, the synergistic mechanisms behind this interplay remain underexplored. This study investigated the synergistic mechanisms by which military defense systems and transportation networks influenced the settlement spatial patterns within China's heritage corridors, using the Guangou section of the Great Wall as a representative case. Through an interdisciplinary approach that integrated historical document analysis, field surveys, remote sensing interpretation, and historical GIS spatial analysis, we constructed a tripartite research framework of "element identification-spatial quantification-mechanism interpretation". Specific analytical methods included: (1) Euclidean distance and viewshed analyses to assess the spatial control exerted by defense facilities; (2) Cost-path analysis and buffer zone analysis to reconstruct historical transportation networks; and (3) Spatial overlay and raster calculation to quantify defense-connectivity interactions. Our findings revealed that settlement evolution underwent three distinct historical phases. Prior to the Ming Dynasty, settlements exhibited a dispersed, "mountain-water adjacent" distribution. During the Ming period, four distinctive settlement types emerged: High Defense-High Connectivity (HDHC) pass-courier station complexes, High Defense-Low Connectivity (HDLC) frontier military zones, Low Defense-High Connectivity (LDHC) plain waterway settlements, and Low Defense-Low Connectivity (LDLC) remote mountainous enclaves. Among these, the Guangou axial zone demonstrated an optimal defense-connectivity synergy model. In the Qing Dynasty phase, spatial configurations transitioned from "defensive control" to "connectivity empowerment", characterized by "linear bead-like" and "planar networked" distribution patterns. This study innovatively proposed a theoretical framework and quantitative indicator system for "defense-connectivity" synergistic evolution. It developed a spatial analysis technical approach that integrated multi-source data fusion and multi-method integration, revealed the evolution patterns and mechanisms of different spatial types in the formation of heritage corridors, and established a spatial management methodology for the protection of linear cultural heritage. Our findings would not only deepen the understanding of the evolution patterns of defensive settlement systems, but also provide precise spatial management references for the "holistic protection" and "living inheritance" of the Great Wall National Cultural Park, offering a replicable analytical framework for global studies on similar heritage corridors.