Introduction to the stone carvings of "Blue Coat Opens the Frontier" in Coiyi Ridge: This stone carving is carved from green sandstone and is located 1.5 kilometers northwest of Wuchi Village, Yongsheng Township, between Hanyuan County, Hongya County and Jinkouhe District. County (district) junction. In 1941, in preparation for war, Chiang Kai-shek rushed to repair the Lexi Highway and engraved two stone monuments "Blue Coat Kaijiang" and "Coiyi Ridge" to commemorate its opening to traffic. The inscription on the inscription is as follows: Coiyi Ridge is the strategic point for transportation between Chuankang and Kang, with an altitude of more than 2,800 meters. It is a must-pass for the Lexi Highway. It is foggy, rainy, and steep, making the construction difficult. This year Qiuzukang was ordered to come here to supervise the work. Due to the tight deadline, the No. 1 stonemasonry team of Tiao Le Department worked hard. Within a few months, the excavation was completed, and the silkworms and birds were covered with trees, and the village became a prosperous village. The employees worked hard and could not let them disappear. Yuan wrote an inscription on the stone to commemorate it.