Shaanxi province's archeologists discovered more than 200 ancient fortresses in Zhen'an county in the Qinling Mountains' hinterlands, during the recent third national cultural relics survey.

According to Li Guang, chief of the county cultural relic management institute, the fortresses are scattered across mountaintops or tucked in hidden places. While small fortresses could only hold several people, more than four large sites could each hold between 400 and 500.

It's the first time such a large number of ancient fortresses have been found in the province, Li says.

According to local records, most were built at the end of the Ming Dynasty (1368-1644) and in the early Qing Dynasty (1644-1911) to protect the wealthy from farmers' uprisings.

"Local celebrities and rich people led the construction of the fortresses, which have the mountains as the base and stones as their walls," Li says. "The forts were easy to guard because three sides of every fortress are on steep slopes, while one side connects the mountain peak."

Zhen'an was the rolling mountain passageway to what are today's Sichuan province and Chongqing municipality to the south, and Hubei province to the east. Because of the dangerous terrain, fortresses were important to protect rich families.