On this day, 27 years ago, on November 9, 1998 (September 21, 1998, the entire Badaling Expressway was opened to traffic. On November 9, 1998, the second phase of the Badaling Expressway project, which lasted one year and nine months, was completed. It was connected with the first phase of the project, making the entire Badaling Expressway open to traffic. The magnificent Badaling Expressway has become Beijing's longest and busiest tourist route. The Badaling Expressway is part of Beijing's National Highway 110 from Zhangjiakou and Datong to Yinchuan. It is also one of the sections of the main national highway from Dandong to Lhasa in Beijing. The Badaling Expressway starts from the Madian Overpass on the Third Ring Road in Beijing, passes through Qinghe, Shahe, and Changping South Exit to Daqiao in Juyongguan. It has a total length of 61.87 kilometers and two-way six lanes. The design speed is 60-120 kilometers per hour. Among them, the first phase of the Badaling Expressway project, Beijing Madian Overpass to Changping, 31.2 kilometers was completed and opened to traffic in 1996. The second phase of the Badaling Expressway project starts from Changping in the south to Badaling in the north, and is 30.67 kilometers. The Badaling Expressway road construction project has a total area of 755,000 square meters and 5.64 million square meters of earth and stone. The bridge project will jointly build 60 large, medium and small bridges, with a total area of 80,000 square meters. Nine new tunnels were built and one was rebuilt in the tunnel project, with a total length of 6108 meters. The protection project is built with slope protection and retaining walls for 20 kilometers, with more than 30 cubic meters of stone masonry, and 28,000 cubic meters of concrete sinking. Among the entire project, the Badaling Bridge is the most spectacular, with a length of 995 meters and a height of 28 meters. A total of 31 bridge piers and 80 cast-in-place piles stand proudly in the ancient river course of Guangou. 217 I-beams flew over the tourist area. One span of 35-meter-long steel beam crossed the railway twice, crossed the highway and the ancient river course of Guangou three times, like an S-shaped ribbon, floating among the mountains. The newly built Tanyugou Tunnel passes under the Great Wall. It has a total length of 3455 meters, a width of 13.1 meters and a height of 7.3 meters. One-way, three-lane tunnel, with its length and width, ranks first among highway tunnels with three lanes and above in Asia and fifth in the world. In the deep mountain Laoyu of the Tanyugou section of the Badaling Expressway, the first steel-arch structure bridge in the history of Beijing City has been erected. It has a total length of 115.5 meters, a width of 13 meters, a height of 23 meters, and an arch span of 80 meters. The four semi-circular steel pipe arches are red, like a "rainbow" falling between the two mountains of Tanyugou. It fills the gap in Beijing's history when there were no steel tube arch bridges. The completion of the Badaling Expressway will effectively alleviate traffic congestion in the northwest of Beijing, drive economic development along the route, promote tourism development, and provide a safe and fast transportation line for Shanxi coal transportation. In particular, the opening of the Badaling Tunnel and Tanyugou Tunnel passing under the Great Wall has separated tourist traffic from transit traffic in the Badaling Great Wall Tourist Area, and the separation of vehicles and tourists has greatly alleviated the situation of vehicle congestion and tourist congestion in the Badaling Chengguan area. In the past, it usually took more than two hours to get to the Badaling Great Wall from Beijing. After the entire Badaling Expressway was opened to traffic, it only took 40 minutes to drive from Madian to Badaling, and the entire journey cost was 20 yuan. It provides a fast, smooth, comfortable and safe transportation channel from downtown Beijing to the Badaling Great Wall Tourist Area. The Badaling Expressway project boldly introduced international advanced technology and equipment and strictly implemented the supervision system. The project pass rate reached 100%, the proportion of excellent products exceeded the national and ministerial standards, and the construction of Badaling Expressway reached the international first-class level.