Aerial photo taken on Aug. 30, 2018 shows the Huixing Expressway threading through the karst landform in Zhenfeng County, southwest China's Guizhou Province. Guizhou has built 5,833 kilometers of expressway by the end of 2017. (Xinhua/Liu Xu)

Aerial photo taken on Aug. 30, 2018 shows the Huixing Expressway threading through the karst landform in Zhenfeng County, southwest China's Guizhou Province. Guizhou has built 5,833 kilometers of expressway by the end of 2017. (Xinhua/Liu Xu)

Aerial photo taken on Aug. 30, 2018 shows the Huixing Expressway threading through the karst landform in Zhenfeng County, southwest China's Guizhou Province. Guizhou has built 5,833 kilometers of expressway by the end of 2017. (Xinhua/Liu Xu)

Aerial photo taken on Aug. 30, 2018 shows the Huixing Expressway threading through the karst landform in Zhenfeng County, southwest China's Guizhou Province. Guizhou has built 5,833 kilometers of expressway by the end of 2017. (Xinhua/Liu Xu)

Aerial photo taken on Aug. 30, 2018 shows the Huixing Expressway threading through the karst landform in Zhenfeng County, southwest China's Guizhou Province. Guizhou has built 5,833 kilometers of expressway by the end of 2017. (Xinhua/Liu Xu)

Aerial photo taken on Aug. 30, 2018 shows the Huixing Expressway threading through the karst landform in Zhenfeng County, southwest China's Guizhou Province. Guizhou has built 5,833 kilometers of expressway by the end of 2017. (Xinhua/Liu Xu)

Aerial photo taken on Aug. 30, 2018 shows the Huixing Expressway threading through the karst landform in Zhenfeng County, southwest China's Guizhou Province. Guizhou has built 5,833 kilometers of expressway by the end of 2017. (Xinhua/Liu Xu)