- According to local legend, long ago when the Vietnamese were fighting Chinese invaders, the Gods sent a family of dragons to help defend the land. This family of dragons began spitting out jewels and jade, which transformed into the thousands of islands and islets dotting the bay, linking together to form a great wall blocking the invaders. With the help of this magical intervention the people defended their land and formed what later became the country of Vietnam. After that, the dragons became interested in more peaceful endeavors and decided to stay to live here. The place where the Mother Dragon flew down was named Hạ Long (Ha: descending, Long: dragon), the place where the dragon children attended to their mother was called Bái Tử Long (Bái: attend to, Tử: children, Long: dragon), and the place where the dragon children wriggled their tails playfully was called Bạch Long Vỹ (Bạch: white - the color of the foam from the wriggling tails, Long: dragon, Vỹ: tail).
- Halong Bay is bordered on the south and southeast by the Gulf of Tonkin, on the north by the China Sea and on the west and southwest by Cát Bà Island. The bay has a 120 kilometer long coastline and is approximately 1,553 square kilometers in size. The bay consists of dense clusters of 1,969 limestone monolithic islands, each topped with thick jungle vegetation, which rise spectacularly from the sea.
- The Bay is host to two ecosystems: a tropical, moist, evergreen rainforest ecosystem and a marine & coastal ecosystem.
- The islands are home to many birds and animals including kites, bantams, monkeys, and iguanas.
- In 1994 Halong Bay was listed as a “World's Natural Heritage” by UNESCO for its outstanding universal aesthetics value. The area designated by UNESCO includes 434 square kilometers with 775 islets.
- Scientists say the bay has experienced at least 500 million years in various geological states: orogeny, marine transgression and marine regression. During the Ordovician and Silurian periods (500-410 million years ago), the bay was deep sea. During the Carboniferous and Permian periods (340-250 million years ago), it was at shallow sea level.
- Several of the islands are hollow and contain small to very large caves. Sung Sot or “Surprise Cave” was discovered by the French in 1901. It is one of the largest grottos in Halong Bay. Its three chambers contain numerous stalactites and stalagmites creating an eerie and enchanting environment. We will visit the cave on the second day of our journey.
- Some of the islands in the bay support floating fishing villages. The fishermen ply the shallow waters for more than 200 species of fish and 450 kinds of mollusks. The largest fishing village, Cua Van, is on our travel itinerary as well.
- Many of the islands have acquired their names as a result of interpretation of their unusual shapes: such as Voi Islet (elephant), Ga Choi Islet (fighting cock), and Mai Nha Islet (roof), in total 989 of the islands have been given names.