Targeting digital-twin security scenarios for large venues, this practice follows the overall approach of “visualized scenes, dynamic resources, and practical applications”. Supported by a Mapmost-based 3D real-scene platform and technologies such as human-in-the-loop mapping, it serves the daily security and major-event command work of the Suzhou Public Security Bureau Industrial Park Branch, enhancing multi-dimensional situational monitoring of major events and real-world security effectiveness.