Recently, the left tube of the Lianfeng Tunnel—the longest tunnel on the Zhaotong Daguan–Yongshan Expressway project—was successfully holed through, marking another major step forward toward the project's full completion and opening to traffic.

The main line of the Dayong Expressway project is 61.691 km long, with a total budgeted investment of RMB 12.6177 billion. It includes 19 bridges and 15 tunnels, with a bridge-to-tunnel ratio of 94.4% along the entire route, making it an important corridor out of Yunnan into Sichuan. The Lianfeng Tunnel is one of the eight control works of the Dayong Expressway, known as the "seven tunnels and one bridge"; its left tube is 10.99 km long and its right tube 11 km. During tunnel construction, the builders overcame difficulties including large water inflow, high working-environment temperatures, and high geological hazard risks, ensuring safe and orderly progress of the project.

As of now, overall progress on the Dayong Expressway has reached 92%, and the tunnels are 95% complete. Once the project opens to traffic along its full length, it will end Yongshan County's history of having no expressway access and achieve Zhaotong City's goal of "expressways in every county."