Tulou are large earthen residential buildings developed in the mountains of southwestern Fujian, where communities adapted communal housing to limited farmland, migration, kinship organization, and insecurity. The World Heritage property includes 46 examples constructed from the fifteenth through twentieth centuries across several counties; Yongding contains prominent clusters at Chuxi, Hongkeng, and Gaobei. Not every Fujian tulou is Hakka, although many in Yongding are closely associated with Hakka clans and histories.

Builders laid stone foundations and raised thick load-bearing walls from compacted earth mixed with local materials. Timber frames, tiled roofs, internal galleries, and rooms surrounded an open courtyard in circular, square, or other enclosed plans. Lower levels commonly held kitchens and storage, with living and sleeping rooms above. Few openings pierced the exterior base, and a controlled entrance aided defense. Wells, ancestral halls, schools, workshops, and shared spaces supported households that could number in the hundreds.

Construction and alteration continued as families prospered, divided, or returned from overseas. Chengqi Lou at Gaobei took its mature form through long building campaigns, while Zhencheng Lou at Hongkeng was completed in the early twentieth century and incorporates stylistic details reflecting wider contacts. The buildings were never standardized fortresses: their dates, plans, internal ownership, decoration, and community histories differ. Daily cooking, worship, marriage, work, and dispute shaped them as lived institutions rather than merely impressive shells.

Political upheaval, economic change, migration, and new housing reduced populations in many tulou during the twentieth century. Some remained occupied; others deteriorated or acquired tourism functions. Conservation has repaired rammed-earth walls, timber members, roofs, drainage, and fire systems, sometimes replacing material too damaged to retain. Visitor paving, signs, shops, electrical services, and railings are modern, and renovated interiors vary in authenticity. An inhabited tulou cannot be managed exactly like an empty monument because safety, privacy, and household needs continue.

UNESCO inscribed the selected Fujian Tulou in 2008 for their communal living tradition, defensive organization, ingenious construction, and relationship with cultivated landscapes. At Yongding, original earthen walls and historic timber survive alongside generations of repair and renewal using compatible methods. Individual rooms may be adapted, reconstructed, closed, or privately occupied, so access does not equal complete preservation of one historical moment. Fire prevention and rainwater control remain essential to conserving mixed earth-and-timber construction. The strongest interpretation presents the clusters as evolving rural neighborhoods whose architecture joined clan life, agriculture, defense, ritual, and migration, while clearly separating historic fabric from recent restoration and tourist presentation.