The product takes "GIS+BIM+IoT" as the starting point to build an open and scalable MapGIS CIM underground space platform product, realizing the integrated management, visual rendering, and processing analysis of all elements of underground space information. It provides a comprehensive product for integrated resource management and sharing, visual display and professional analysis, rapid application construction, and global linkage for the informationization construction of underground space. The platform is built using the "1+1+N" model to create a unified digital base for underground spaces, and to build specialized applications at different business levels to provide services for the construction of underground spaces.