In the context of China’s New Urbanization Strategy, it is of great practical significance to study rural–urban population migration from the perspective of house purchases by rural households. In this paper, the Huai’an Rural Survey Dataset (872,414 households) was used to study the heterogeneity of rural households’ house purchases in different classes of urban destinations, and its influencing factors were analyzed with GeoDetector. The results show that the urban house purchase destinations preferred by farmers were county towns, townships, foreign cities, and metropolitan areas, indicating that in situ urbanization has become the main path of urbanization for farmers in Huai’an. Among the environmental influencing factors, the rural environment had the greatest influence on house purchases locally (in the township and county town), and this influence decreased with the outward shift of house purchase destinations. The housing environment, the settlement environment, and the population and family environment were the main environmental impact elements. The natural environment and the policy environment had little influence on the house-purchasing behavior of farmers, and the location environment was critical in exotic locations (metropolitan areas and foreign cities). Therefore, this paper argues that a higher demand for housing is growing in China’s less developed rural areas, creating a situation in which the metropolitan area is the core and the county town is the main contributor. In terms of policy improvements, it is important to pay more attention to small cities such as counties and to offer housing concessions and welfare to “new citizens” from rural areas, as well as to significantly improve the housing, earnings, and public service environment for those who prefer to stay in the countryside.

In the context of China’s New Urbanization Strategy, a growing number of cities are beginning to experience significant changes in their intra-city structure and size distribution, but systematic research is still lacking. This paper investigated the intra city-size distribution of 214 cities in China’s Yangtze River Delta Region (YRDR) from 1990 to 2020. The study used the Pareto index to portray the equalization differences in intra city-size distribution, and investigated the heterogeneity of its influencing factors using multiscale geographically weighted regression (MGWR). The results showed that most of the cities in the YRDR had a city-size distribution consistent with a Pareto distribution but still tended to be polarized. Among them, the better-developed large cities and regions were more consistent with the Zipf distribution, as were the county-level cities and prefecture-level cities. In terms of spatio-temporal distribution, the intra city-size distribution showed a spatial agglomeration pattern of “polarization in the west and equalization in the east” and the scope and intensity of cold and hot spots reduced. Regarding driving factors, land, industry, and population were essential influences on the intra city-size distribution. Of these, the natural environment and location were important global influencing factors, and economic and social factors only had a more significant influence in 1990 and 2020. The impact of industry restructuring gradually increased, and the population was a significant influence only in the early years. By exploring the intra city-size distribution, this paper provides a scientific basis for the optimization of town structure and policy formulation in small and medium-sized cities, and some new concerns have been proposed.