Research on the spatial distribution characteristics of historic districts in small towns in the Hangzhou–Jiaxing–Huzhou area based on a comprehensive information database

This study reviews the formation and evolution of historic districts in small towns of the Hangjiahu area and defines the research scope in time, space, and type. From 334 small towns, we identify 89 evidence-based historic districts formed mainly before 1949, excluding post-1949 “heritage-style” new streets and undocumented cases, and compile the Hangjiahu Small Town Historic Districts Directory. A Comprehensive Information Database with nine linked sub-databases (unified districtᵢd) is established; its geographic information sub-database supports spatial analysis using kernel density estimation, Ripley’s K with Monte Carlo envelopes, and Geodetector with terrain-stratified enrichment ratios and 999-permutation tests, incorporating historically grounded functional, administrative, and formation-period proxies from the textual attribute database. Results show: (1) historic districts form an inwardly concentrated pattern with clear directional tendencies; (2) several high-density cores are identified, with Monte Carlo CSR tests (999 runs) indicating significant clustering at 1. 63–3. 27 km and 11. 44–24. 51 km; (3) a “sparser west–denser east, fewer south–more north” pattern reveals strong clustering, pronounced spatial imbalance, and large regional differences. The study offers planning-grade information and illustrative workflows to support county- and municipal-level conservation zoning, revitalization planning, and coordinated heritage management.