A visitor takes photos at the Imperial Summer Resort in Chengde, north China's Hebei Province, Oct. 23, 2018, the day of the First Frost. (Photos: Xinhua)

First Frost, also known as Shuangjiang, is one of the 24 solar terms of the Chinese lunar calendar.

Tourists visit a scenic area in Miaozi Town of Qingzhou, east China's Shandong Province, Oct. 23, 2018.

A bird is seen on a tree branch in the mountains of Zhushan Town in Yuan'en County, central China's Hubei Province, Oct. 23, 2018.

A reaper harvests rice at a farm in Yongfeng County, east China's Jiangxi Province, Oct. 23, 2018.

Tourists visit the Hukou waterfalls in Jixian County of Linfen City, north China's Shanxi Province, Oct. 23, 2018.

Tourists visit the Mingxiaoling Mausoleum in Nanjing, east China's Jiangsu Province, Oct. 23, 2018.

Tourists visit the Zhangye National Wetland Park in Zhangye, northwest China's Gansu Province, Oct. 23, 2018.

Tourists visit Taihu Garden Expo Park in Suzhou, east China's Jiangsu Province, Oct. 23, 2018.

Tourists visit the Tianyige Pavilion in Ningbo, east China's Zhejiang Province, Oct. 23, 2018.

First Frost, also known as Shuangjiang, is one of the 24 solar terms of the Chinese lunar calendar.