Chittagong Division
Chittagong Division, officially known as Chattogram Division, is geographically the largest of the eight administrative divisions of Bangladesh. It covers the south-easternmost areas of the country, with a total area of  and a population at the 2022 census of 33,202,326. The administrative division includes mainland Chittagong District, neighbouring districts and the Chittagong Hill Tracts. Chittagong Division is home to Cox's Bazar, the longest natural sea beach in the world; as well as St. Martin's Island, Bangladesh's sole coral reef. History
The Chittagong Division was established in 1829 to serve as an administrative headquarters for five of Bengal's easternmost districts, with the Chittagong District serving as its headquarters. During the East Pakistan period, the division's Tippera district was renamed to Comilla District in 1960. In 1984, fifteen districts were created by separating and reducing the original five districts of Chittagong, Comilla, Hill Tracts, Noakhali and Sylhet:
The Chittagong District was divided into two districts; Chittagong and Cox's Bazar District
The Comilla District was split into three districts; Comilla, Brahmanbaria and Chandpur
The Hill Tracts District was split into three districts; Bandarban, Khagrachhari and Rangamati
The Noakhali District was divided into three districts; Noakhali, Lakshmipur and Feni
The Sylhet District was split into four districts; Sylhet, Habiganj, Moulvibazar and Sunamganj. Sylhet, Habiganj, Moulvibazar and Sunamganj district ceded from the Chittagong Division to join a newly-established Sylhet Division in 1995. Administration
Chittagong Division is presently subdivided into eleven districts (zilas) and thence into 100 sub-districts (upazilas). The first six districts listed below comprise the north-western portion (37.6%) of the division, while the remaining five comprise the south-eastern portion (62.4%), the two portions being separated by the lower (or Bangladeshi) stretch of the Feni River; the upland districts of Khagrachhari, Rangamati and Bandarban together comprise that area previously known as the Chittagong Hill Tracts. Demographics 

According to the 2022 Census of Bangladesh, Chittagong Division had 7,528,333 households and a population of 33,202,326, 33.7% of whom lived in urban areas. The population density was 979 people per km2. 90.11% were Muslims, 6.61% Hindus, 2.92% Buddhists, 0.22% Christians and 0.14% others. 