Aerial photo taken on July 24, 2021 shows the Yachihe Bridge of Guiyang-Qianxi Expressway in Southwest China's Guizhou Province. Southwest China's Guizhou, a mountainous province boasting over 20,000 bridges among its karst mountains, is dubbed "the museum of bridges" due to the vast numbers, various types and complex technologies of the bridges built over the decades. (Photos: Xinhua)

Aerial photo taken on July 23, 2021 shows the Yachihe Bridge of Guiyang-Qianxi Expressway in Southwest China's Guizhou Province. The bridges, dozens are world record class works, creating thoroughfares by spanning gorges, deeply integrated the province into the nation's transportation network and brought great improvement to the local residents' quality of life.

Aerial photo taken on July 23, 2021 shows the Yachihe Bridge of Guiyang-Qianxi Expressway in Southwest China's Guizhou Province.

Aerial photo taken on July 23, 2021 shows the Yachihe Bridge of Guiyang-Qianxi Expressway in Southwest China's Guizhou Province.

Aerial photo taken on July 21, 2021 shows Qianchun Overpass in Guiyang, Southwest China's Guizhou Province.

Aerial photo taken on Aug. 9, 2021 shows a mega bridge of the Pingtang-Luodian Expressway in Southwest China's Guizhou Province.

Aerial photo taken on Jan. 18, 2021 shows the Yunwu Bridge in Southwest China's Guizhou Province.