Core Points - The Zhuhai Tunnel has reached a significant milestone with the successful sealing of the last top slab at the junction of the "underwater tunnel" and "mountain tunnel," marking the completion of the main structure [1] - This key transportation project is expected to facilitate the opening of the main line by the end of the year, enhancing connectivity in the region [1] Group 1: Project Details - The junction between the underwater and mountain tunnels is located between the Gua Ding Jiao Mountain and the Mo Dao Men Waterway, with a total length of approximately 170 meters and a maximum width of nearly 50 meters [1] - This section of the project was the earliest to commence and the latest to complete, highlighting its complexity [1] Group 2: Environmental and Safety Considerations - The construction area is near a water source protection zone and a water supply pipeline to Macau, necessitating strict adherence to environmental protection standards throughout the project [1] - The project manager emphasized the importance of ensuring safety and quality while accelerating subsequent construction efforts to achieve an early opening [1] Group 3: Impact on Transportation - Once operational, the Zhuhai Tunnel will complement the Zhuhai Bridge, creating a "North Bridge South Tunnel" layout that is expected to significantly alleviate traffic pressure on the Zhuhai Bridge and improve east-west traffic efficiency in the city [1]