Aerial photo taken on Sept. 9, 2021 shows a mountain road popularly known as the "Taihang Sky Road" in Pingshun County, north China's Shanxi Province. (Photo: Xinhua)

Aerial photo taken on Sept. 9, 2021 shows a mountain road popularly known as the "Taihang Sky Road" in Pingshun County, north China's Shanxi Province.

Aerial photo taken on Sept. 9, 2021 shows a mountain road popularly known as the "Taihang Sky Road" in Pingshun County, north China's Shanxi Province.

Aerial photo taken on Sept. 9, 2021 shows a mountain road popularly known as the "Taihang Sky Road" in Pingshun County, north China's Shanxi Province.