The Holy See (Tòa Thánh) and the Holy City (Thánh Địa) as well as the original center of the Cao Đài Religion are in the province of Tây Ninh, which is about 100 kilometers northwest of Saigon. The Holy City, an area of about 20,328 hectares, is divided into 18 sections or neighborhoods and is administered by the Church. The Holy See is the site of the Main Temple (Đền Thánh), the main administrative offices, residences for high dignitaries and disciples working on the grounds, a hospital, a school, an orphanage, a home for the aged, and other major facilities. 

Hundreds of Cao Đài Temples/ Thánh Thất (or Holy Houses) are scattered all over Vietnam, especially in the countryside of southern and central Vietnam. There are many Caodaist communities in Cambodia as well as in the United States, Canada, France, Germany, Australia and other countries as a result of the refugee exodus from Vietnam since 1975.