Vietnam's culture has developed over the centuries from indigenous ancient Đông Sơn culture with wet rice cultivation as its economic base. Some elements of the nation's culture have Chinese origins, drawing on elements of Confucianism, Mahāyāna Buddhism and Taoism in its traditional political system and philosophy. Vietnamese society is structured around ''làng'' (ancestral villages); all Vietnamese mark a common ancestral anniversary on the tenth day of the third lunar month. The influence of Chinese culture such as the Cantonese, Hakka, Hokkien and Hainanese cultures is more evident in the north where Buddhism is strongly entwined with popular culture. Despite this, there are Chinatowns in the south, such as in Chợ Lớn, where many Chinese have intermarried with Kinh and are indistinguishable among them. In the central and southern parts of Vietnam, traces of Champa and Khmer culture are evidenced through the remains of ruins, artefacts as well within their population as the successor of the ancient Sa Huỳnh culture. In recent centuries, Western cultures have become popular among recent generations of Vietnamese.