Blowhard, Esq. writes:

The mountainous areas of western Fujian province in southwest China are home to a unique form of rammed-earth building known as tulou — large defensive structures designed to contain and protect one family clan…

…These enclosed fort like buildings, which could take seven years to build, have rounded stone foundations and a base of large stones, plastered with clay, which support 6-foot-thick earth walls, reinforced with bamboo canes. The building’s interior is a largely wood structure of beams, decks, and columns, which contains 250 small uniform dwelling units, housing some eighty families. These face a central communal courtyard, in which an ancestral shrine provides a focus for the entire community…

– Building Without Architects: A Global Guide to Everyday Architecture