Earthen houses(Tulou) represent a vernacular architecture specific to Jiangxi, Fujian and Guangdong provinces following the flow of the Hakka people from central China to the South. The architecture is a building style in southern China unique to the Hakka people. The Tulou are either round or square, and were designed as a large fortress and apartment building in one. Structures typically had only one entranceway and no windows at ground level. Each floor served a different function - the first hosts a well and livestock, the second is for food storage and the third and higher floors contain living spaces. The architectural structure, carvings, pillar couplets of these dewelling houses reflect the wisdom of the Hakkas. The older examples of this style of construction consist of interior buildings enclosed by huge peripheral ones holding hundreds of rooms and dwellers. With all the halls, storehouses, wells and bedrooms inside, the huge towerlike building functions almost as a small fortified city. Earthen houses are made of earth, stone, bamboo and wood, all readily available materials. After constructing the walls with rammed earth, branches, strips of wood and bamboo chips were laid in the wall as "bones" to reinforce it. The end result is a well lit, well-ventilated, windproof, quakeproof building that is warm in winter and cool in summer.

Over twenty thousand of these houses still stand today, ten of which are over 600 years old. The oldest one, “Fu Xing Lou” in Hu Le town, was constructed over 1,200 years ago and is regarded as a “living fossil” of the construction style of central China. The Tulou located at the border of Yongding County and Nanjing County is the perfect example of this style of construction. Thousands of these buildings were built in the Qing Dynasty, with thick walls, ingenious structures and various functions such as protection against high winds, earthquakes and hot and cold weather. They also served as a guard against enemies. All these buildings were furnished for living, storage and cooking and can accommodate a clan of hundreds of family members to live a happy life together.