["Transactions in GIS, Volume 30, Issue 5, August 2026. ", "\nABSTRACT\nAs globalization and urbanization intensify, human expansion continues to intensify. Focusing on Chongqing's main urban area, this study uses point‐of‐interest (POI) density to quantify urban vitality (UV) and assess urban centralization. A UV index captures spatial variation across traffic analysis zones (TAZ), with centralization examined by POI themes and categories, while an XGBoost model predicts urban center distribution. Results show multiple dynamic centers emerging in peripheral areas, indicating a marked shift toward polycentric centralization. POI category concentration peaks near the city center and declines outward; however, the overall spatial structure reflects a polycentric distribution characteristic of mountainous cities. The UV index further shows decreased high‐vitality TAZs and increased low‐ and medium‐vitality zones, similar to patterns in Hong Kong. Overall, mountainous cities exhibit a clear shift toward multi‐center development. City managers should thus pay greater attention to human expansion's impacts on future urban development.\n"]