Paikend was once a core city of the Bukhara oasis, renowned as the "Copper City" for its robust defense systems and strategic position. However, due to water resource depletion and geopolitical changes, Paikend gradually declined, and Bukhara rose to replace it as the regional center. Bukhara achieved its key position in Central Asia through a more sophisticated defense system, closer proximity to the Zerafshan River, and political and cultural innovations. The rise and fall of Paikend and Bukhara were not only closely tied to natural resources but were also deeply influenced by changes in geopolitical and military dynamics. The designation of "Copper City" symbolizes the defensive ingenuity and cultural heritage of oasis cities. While Paikend’s formidable walls represented an earlier singular defensive model, Bukhara transitioned to a comprehensive strategy through its triple-layered defense structure. By comparing the two cities, this study aims to reveal the dynamic changes of Central Asian oasis cities in terms of natural environment, technological innovation, and cultural integration, providing a new perspective on the historical development of this region
