Core Points - The successful completion of the last rock barrier at the Gongting No. 2 Tunnel marks the full connectivity of all seven tunnels in the Dahuajia (Gansu-Qinghai Border) to Qingshui section highway project [1] - The Gongting No. 2 Tunnel features a left line of 2060 meters and a right line of 2075.297 meters, with maximum depths of approximately 323 meters and 334 meters respectively [1] - The project is part of the National Highway Network Planning (2013-2030) and is crucial for enhancing the regional road network and promoting economic development along the Yellow River [2] Company and Industry Summary - The Qinghai Provincial Transportation Holding Group Co., Ltd. reported the successful breakthrough of the Gongting No. 2 Tunnel, which utilized advanced geological forecasting to monitor rock conditions and ensure construction safety [1] - The highway project spans 29.443 kilometers and connects with major highways, facilitating inter-provincial transportation and supporting the national strategy for western development [2] - The completion of this project is expected to significantly improve the transportation infrastructure in Qinghai, contributing to the high-quality development of the Lanzhou-Xining urban agglomeration and the tourism resources along the Yellow River [2]