The chapter expands the analysis by comparing and contrasting urban and rural patterns across different environmental zones of the Roman Campagna, focusing specifically on the role of villa architecture. Whereas in the tuff region closer to Rome concrete construction lagged behind the early phase of the technique in the metropolis, the limestone architecture in the territory of neighboring Tibur shows a more complex pattern, reflecting how the diffusion of monumental rural residence in areas with easier access to both key ingredients for high-quality mortars, volcanic ash and lime, could have triggered technological change.