The tulou in the Fujian Province is divided into three types, Wufeng [Five phoenix], Rectangular, and Round. Wufeng are located mainly in Yongding, and rectangular and round tulou are distributed in Nanjing, Pinghe, Zhaoan West and Yongding East. In most of the villages, round and rectangular tulous are mixed together. In studying the origin of tulou, a question arise: which shape came first, the round or the rectangular. The scholar Huang Hanmin gave us a conclusion, the rectangular tulous were the original ones.
The Hakka were a part of the Han ethnic group. When migrating, they gradually changed their vernacular architecture by incorporating the original Han architecture into the local conditions, and produced the tulou, this spectacular architectural form.
The Wufeng tulous are obviously the results of a redesign of the Chinese courtyard by the Hakkas. 'Three halls and two side rooms' are a feature of the Wufeng tulou. The side rooms are the heightened wing-room of the Chinese courtyard. The center hall in the back yard becomes a multi-storey building. The earth walls in the four sides are enclosure. This was not only for defence reasons, but also as an expression of traditional Chinese architectural forms.
The Five phoenix tulou
From the topography of the plain to the topography of the hill, the Wufeng tulou tended to decrease while the rectangular tulous are increased. The rectangular tulou has higher and closer walls. The transformation from Wufeng to rectangular tulou was the process of fortifying the walls and simplifying the roof and structures.
The Rectangular tulou (Multi-complex group)
The Rectangular tulou (Castle style)
In reality, the rectangular tulous were built earlier than round ones. For example, in the northern part of the Guzhu, Yongding, the rectangular tulou, named Wuyun tulou was built five or six hundred years ago, while the round shape, Chengqi had only been built for three or four hundred years.
The round and rectangular tulou (Bird-eye view)
In western Nanjing, the total number tulous is 408: there are 280 rectangular tulous, 128 round tulous. 43 percent of the rectangular tulous were built during the eighteen's and nineteen's. However, 95 percent of the round tulous were built in last century. Among these, 63 round tulous were built after 1960.
The tulou group in Nanjing