Cát Hải
Cát Hải[Sun Group (Vietnam)|] is an archipelago in the Gulf of Tonkin. Its full name is Cát Hải Special Zone of Hải Phòng City belonging to Hải Phòng city in the Red River Delta of Vietnam.
History
Its name Cát Hải means "Cát Bà Long Châu Hải Dương Thương Chính Quan Phòng" in common Middle-age Annamese language.All Cát Hải area's knowledge before the 18th century was legendary and had very little things recorded by royal historians. However, according to the administrative documents of Hải Phòng city, this territory in the past included two archipelagos as Các Bà and Cửa Đức Ông. Over time, those names were wrongly called by folk to become Cát Bà and Long Châu.
Middle Ages
According to Đồng Khánh địa dư chí lược, at the beginning of the 19th century, the territory of Cát Hải rural district was two cantons Đôn Lương and Hà Liên, belonging Hoa Phong rural district, Sơn Định prefecture, Quảng Yên province. Nghiêu Phong district has many different names: Động Phục Long, Ân Phong, Chi Phong. Until the first year of Thiệu Trị, it was renamed Nghiêu Phong to avoid the real name of Dowager Queen Hồ Thị Hoa.Since the years of Đồng Khánh, Nghiêu Phong rural district has included three cantons Đôn Lương, Hà Liên and Vân Hải.
20th century
On August 19, 1890, Tonkinese viceroy Hoàng Cao Khải issued a decree to change Nghiêu Phong from a rural district into a prefecture. Because of that, Vân Hải canton has been raised to Vân Hải rural district, at the same time, Đôn Lương was merged with Hà Liên to become Cát Hải rural district. Its capital seated in Cát Bà street, where was later expanded to the township, then the town.The territory of Cát Hải island district only consisted of two archipelagos Cát Bà and Long Châu. In particular, the area of Cát Bà island was almost the area of the special zone.
21st century
On April 22, 2025, to meet promptly the plan to arrange and merge administrative units by the Government of Vietnam, the People's Committees of Hải Dương province and Hải Phòng City passed a resolution on the dissolution of all rural-district level administrative units in new Hải Phòng City, followed by another Resolution on the merger of communes and the establishment of new communes with their new names.According to the political document officially published for the press, Cát Hải island-district was also dissolved. The entire area and demography have been transformed to commune-level administrative unit, which is called as Cát Hải Special Zone of Hải Phòng City. Cát Hải special zone is directly under the management of expanded Hải Phòng City.
Geography
As of 2018 the Cát Hải special zone had a population of 43,187. The special zone covers an area of. Its capital lies in Cát Bà Island.Economy
The islands are subject to major land developments. VinFast has built an automobile factory on the Southern half of the island, andSun Group is developing a holiday resort on the northern half. A 5.44 km long bridge - the longest sea crossing in Vietnam - connects the island to Hai Phong.