The results show that there are 15 vestiges of ancient people such as Eo Bua cave in Hien Hao commune, Tung Ba of National Park, Bo Da, Khoai Mui of Tran Chau commune, Ang Giua of Viet Hai commune. In particular, the site of Cai Beo was discovered by a French archaeologist in 1938, through repeated excavations and results of carbon dioxide analysis that said the ancient Vietnamese were present more than 6,000 years ago today. In the upper soil layer of Cai Beo vestige, there is also a relic floor containing typical relics of Ha Long culture. In this soil layer there are few animal bones. The artifacts here bring all kinds of Ha Long culture and also have specific characteristics that show that people of Ha Long came here to live at a late stage, high development stage of the culture. this. Between the two upper and lower layers of Cai Beo site is a thin leveling layer that does not contain relics or bones of animals. This proves that there was a time when the sea level rose to flood the lower layer, leaving traces of the sea separating the two cultures early and late. Cai Beo vestige has a great historical value affirming that the ancient Vietnamese people have lived in this land since ancient times. People on the island for many generations.

The story goes that for a long time, this rocky island was once a base for the women to grow, gather, provide food for the men ahead to fight the enemy, when they came to conquer the island. Also from this battle appeared many brave female generals, so the ancient people named the island Ba Ba Island and later called it as Cat Ba Island. Also from this traditional name, women have always played a role in building and protecting the island district ever since. The names of Phu Long sand, Dau Voi mountain, Phuong river ... each place is a majestic legend. The islanders can be proud of their traditions.

Cat Ba Island was once the base of many uprisings. In 1750, farmer leader Nguyen Huu Cau rebelled against the Trinh feudalist regime that took Cat Ba island as a base. When the Nguyen court sold the country to France, the people of the island were as resentful as the resentment of the people in the country. In 1893 when French troops landed on Cat Ba Island, fishermen on the island organized fierce fighting. In the beginning, there was Hoang Thong Te's uprising, the son of Tran Chau village erected the insurrection flag against the act of selling the country of the Nguyen Dynasty (in 1873 - 1874). From Cat Ba land, where the insurgents went, the feudal mandarins were smashed there, the stronger they fought. When the uprising spread to Quang Yen - Hai Duong overflowing into Thai Binh, the Nguyen court had to concentrate its forces to cope. On the sea, Hoang Thong Te's younger sister, Hoang Lan Vu, also mobilized an army along the coast to match the army of Hoang Thong Te in Thai Binh. Facing the power of the imperial army, the uprising of the two brothers Hoang Thong Te and Hoang Lan Vu was suppressed. This uprising affirmed the patriotism, the brave spirit of the islanders in general and Cat Hai women in particular.

In the years 1889 - 1893, the movement against French colonial aggression of the Tonkin people intensified. French colonialists and feudal dynasties cracked down on the movement. Tien Duc, a leader of the coastal insurgents who retreated to Cat Ba island, built and fortified his army, the rugged mountainous region of Cat Ba became one of the main bases of the insurgency. Tien Duc relied on the topography of Trung Trang, Mai Go, Tra Bau areas to build plantations, medium and rear posts. The whole base was guarded like a fortified battlefield with rocky trap. People on the island actively participated in the movement of insurgents. Tien Duc chose some local people in its army to assign important tasks.

Cat Hai island district as well as so many rural areas of our country, in the history of building and defending the country, each page is soaked with blood, sweat and tears. Since the dawn of the nation's construction, Cat Hai has had beautiful front pages, ancient Vietnamese who have lived on this land. Cai Beo vestige is proof.