San Chay ethnic group
Name of ethnic group: San Chay (Cao Lan, San Chi, Man Cao Lan, and Hon Ban).
Population: 147,315 people (Year 1999).
Locality: Concentrated in Tuyen Quang, Thai Nguyen, and Bac Giang provinces. Communities of San Chay are also found scattered in Quang Ninh, Yen Bai, Lang Son, and Vinh Phuc provinces.

Customs and habits
 - Ancestral worship is widely practiced but is influenced by Buddhism, Taoism, and Confucianism. Houses are usually built level to the ground. The San Chay house is said to resemble the "Buffalo Genie", the four pillars of the house symbolize the four legs of the buffalo, the paths around the house represent the ribs, and the roof represents the backbone. One of the two corners of the penthouse is usually used as the altar for the ancestors and is regarded as the holiest section of the house.

 - The San Chay inhabitants belong to various family lineages, each lineage having several branches. The father is the head of the family. After a wedding, the wife lives with her parents and she settles permanently at the husband's house only after her first childbirth.

Culture
 - The language of the San Chay is classified with the Tay-Thai Group. The San Chay have many old tales, folksongs, proverbs, and sayings. A particularly popular cultural activity is the "sinh ca", an alternating love song chant. Their musical instruments include castanets, small copper bells, cymbals, wind instruments, and drums.

Costumes
 - The modern attire of the San Chay tends to resemble the Kinh or Tay.

Economy
 - The San Chay cultivates wet rice and agriculture, which plays an important role in their livelihood.