Aerial photo taken on July 23, 2019 shows a road through mountains in Anyang Town of Du'an Yao Autonomous County, south China's Guangxi Zhuang Autonomous Region. The total mileage of roads in Du'an reaches 3,583 kilometers. (Xinhua/Lu Boan)

Aerial photo taken on July 23, 2019 shows roads at Qinqi Village in Longwan Township of Du'an Yao Autonomous County, south China's Guangxi Zhuang Autonomous Region. The total mileage of roads in Du'an reaches 3,583 kilometers. (Xinhua/Lu Boan)

Aerial photo taken on July 23, 2019 shows a winding mountain road in Longwan Township of Du'an Yao Autonomous County, south China's Guangxi Zhuang Autonomous Region. The total mileage of roads in Du'an reaches 3,583 kilometers. (Xinhua/Lu Boan)

Aerial photo taken on July 23, 2019 shows a winding mountain road in Longwan Township of Du'an Yao Autonomous County, south China's Guangxi Zhuang Autonomous Region. The total mileage of roads in Du'an reaches 3,583 kilometers. (Xinhua/Lu Boan)

Aerial photo taken on July 23, 2019 shows roads along the banks of the Hongshui River in Longwan Township of Du'an Yao Autonomous County, south China's Guangxi Zhuang Autonomous Region. The total mileage of roads in Du'an reaches 3,583 kilometers. (Xinhua/Lu Boan)

Aerial photo taken on July 23, 2019 shows a road linking with the Lanhai Expressway in Anyang Town of Du'an Yao Autonomous County, south China's Guangxi Zhuang Autonomous Region. The total mileage of roads in Du'an reaches 3,583 kilometers. (Xinhua/Lu Boan)

Aerial photo taken on July 23, 2019 shows bridges across the Hongshui River in Du'an Yao Autonomous County, south China's Guangxi Zhuang Autonomous Region. The total mileage of roads in Du'an reaches 3,583 kilometers. (Xinhua/Lu Boan)

Aerial photo taken on July 23, 2019 shows roads along the banks of the Hongshui River in Longwan Township of Du'an Yao Autonomous County, south China's Guangxi Zhuang Autonomous Region. The total mileage of roads in Du'an reaches 3,583 kilometers. (Xinhua/Lu Boan)