Wikipedia
Diaolous are fortified multi-storey watchtowers, generally made of reinforced concrete. These towers are located mainly in Kaiping County, Guangdong province, China.
The first towers were built during the early Qing Dynasty, reaching a peak in the 1920s and 1930s, when there were more than three thousand of these structures. Today, approximately 1,833 diaolou remain standing in Kaiping, and approximately 500 in Taishan. They can also occasionally be found in numerous other areas of Guangdong, such as Shenzhen and Dongguan. Although the diaolou served mainly as protection against forays by bandits, a few of them also served as living quarters.
Kaiping has traditionally been a region of major emigration abroad, and a melting pot of ideas and trends brought back by overseas Chinese. As a result, many diaolou incorporate architectural features from China and from the West.
In 2007, UNESCO named the Kaiping Diaolou and Villages (开平碉楼与村落) in China as a World Heritage Site. UNESCO wrote, "...the Diaolou ... display a complex and flamboyant fusion of Chinese and Western structural and decorative forms. They reflect the significant role of émigré Kaiping people in the development of several countries in South Asia, Australasia, and North America, during the late 19th and early 20th centuries, and the close links between overseas Kaiping and their ancestral homes. The property inscribed here consists of four groups of Diaolou, totaling some 1,800 tower houses in their village settings."