<p>Underground space detection serves as the initial step in underground space development, where high precision and comprehensive results are always prioritized. However, as single detection method can sometimes fail to accurately identify complex geological conditions, here we utilized a multifaceted underground space detection approach, based on 2200 meters of core samples, focusing on Qianjiang New Town in the central area of Hangzhou, a major city in China. First, we integrated high-density electrical methods with multi-source seismic surveys (including surface and body wave analysis) to achieve refined stratigraphic layering of the Hangzhou formation. Subsequently, we employed in situ geotechnical parameter monitoring and inversion techniques, combined with hyperspectral core scanning, to characterize the composition and mechanical properties of borehole samples. Finally, three-dimensional (3D) laser scanning technology was applied to construct a detailed 3D geological model of the Qianjiang New Town core area. Our approach used a suitable combination of detection technologies to mitigate limitations and enhance detection accuracy, allowing a comprehensive and accurate understanding of the stratigraphy and lithology data from the Qianjiang New Town. Integrating these data with 3D models of structures in the core area enables city decision-makers to consider the stratigraphy, lithology, and attributes of structures and surrounding areas comprehensively. Furthermore, our approach provides a replicable template for comprehensive underground detection in other major cities.</p>