People take photos of the city wall in Xi'an, northwest China's Shaanxi Province, Oct. 13, 2025. After the continuous autumn rain, moss and other plants have covered the city wall with a green coat, attracting people to watch and take photos.

The 13.74-kilometer-long ancient city wall that surrounds Xi'an is one of the longest and best-preserved of its kind in China. (Xinhua/Shao Rui)

An aerial drone photo taken on Oct. 13, 2025 shows people walking along the city wall in Xi'an, northwest China's Shaanxi Province. After the continuous autumn rain, moss and other plants have covered the city wall with a green coat, attracting people to watch and take photos.

The 13.74-kilometer-long ancient city wall that surrounds Xi'an is one of the longest and best-preserved of its kind in China. (Xinhua/Shao Rui)

A woman poses for a photo with the city wall in the background in Xi'an, northwest China's Shaanxi Province, Oct. 13, 2025. After the continuous autumn rain, moss and other plants have covered the city wall with a green coat, attracting people to watch and take photos.

The 13.74-kilometer-long ancient city wall that surrounds Xi'an is one of the longest and best-preserved of its kind in China. (Xinhua/Shao Rui)

A woman poses for a photo with the city wall in the background in Xi'an, northwest China's Shaanxi Province, Oct. 13, 2025. After the continuous autumn rain, moss and other plants have covered the city wall with a green coat, attracting people to watch and take photos.

The 13.74-kilometer-long ancient city wall that surrounds Xi'an is one of the longest and best-preserved of its kind in China. (Xinhua/Shao Rui)

People walk along the city wall in Xi'an, northwest China's Shaanxi Province, Oct. 13, 2025. After the continuous autumn rain, moss and other plants have covered the city wall with a green coat, attracting people to watch and take photos.

The 13.74-kilometer-long ancient city wall that surrounds Xi'an is one of the longest and best-preserved of its kind in China. (Xinhua/Shao Rui)

A drone photo taken on Oct. 13, 2025 shows a girl viewing the city wall in Xi'an, northwest China's Shaanxi Province. After the continuous autumn rain, moss and other plants have covered the city wall with a green coat, attracting people to watch and take photos.

The 13.74-kilometer-long ancient city wall that surrounds Xi'an is one of the longest and best-preserved of its kind in China. (Xinhua/Shao Rui)

People walk along the city wall in Xi'an, northwest China's Shaanxi Province, Oct. 13, 2025. After the continuous autumn rain, moss and other plants have covered the city wall with a green coat, attracting people to watch and take photos.

The 13.74-kilometer-long ancient city wall that surrounds Xi'an is one of the longest and best-preserved of its kind in China. (Xinhua/Shao Rui)

A man takes a photo of the moss on the city wall in Xi'an, northwest China's Shaanxi Province, Oct. 13, 2025. After the continuous autumn rain, moss and other plants have covered the city wall with a green coat, attracting people to watch and take photos.

The 13.74-kilometer-long ancient city wall that surrounds Xi'an is one of the longest and best-preserved of its kind in China. (Xinhua/Shao Rui)