A brief reprise of the geological aspects, organization, physical constraints, and appearance of each city will remind us of their common and unique features. Then we can compare them by groups linked by research questions. Agrigento is built on two ridges of 120 and 320–390 m, setting generous limits not yet filled by the modern city. A plain extends from the lower ridge south to the sea. Vistas were provided along contours and across elevations. Grouping the public buildings on stony ridges, with temples above and below and government structures along the west side, made economic and aesthetic sense. Landslides provide important clues to the nature of the hill the city is built on, and they correlate with occupation of various parts of the site. Additionally, the water system shows unexpected correlation with the families of discontinuities in the stone rather than the surface grid of the streets (Ercoli and Crouch 1998; Crouch 1989). Morgantina stretches along a ridge about 600 m in elevation. The agora most clearly reveals the interface of urban design and geology. Sanctuaries and fountains were the focus during the fifth century B. C. E. In the third century, modest but elegant new architecture (theater, great steps, flanking stoas, fountains, sanctuary) combined with pragmatic engineering as framework and connector between points of observation. Morgantina had one aqueduct, from the springs that later supplied Aidone. The site has numerous springs although some are now dry or give less than 1 l/s. Yet, during the third century B. C. E. when the population was at its maximum, the aquifer was also at maximum, and higher springs were fed from it more amply than at present. Improper management of water resources likely hastened the demise of the town after the Roman conquest. At the turn of the era, the shift from small rural towns to great landed estates as centers of population affected Morgantina strongly. Deforestation of the hills and mountains for fuel and building materials could have resulted in desiccation, with climate change a related factor. Occupation by the Hispanii (Spanish veterans) who replaced the Hellenized Sicilians after 211 B. C. E. coincided with a negative water balance.