Dark and Bright Cave is one of the largest and the most beautiful caves on Halong – Lan Ha Bay. Nothing is more enjoyable than free kayaking on the crystal blue water and then find yourself under the low roof of the cave. Dark and Bright Cave is located where Lan Ha Bay meets Halong Bay and it belongs to Cat Ba Biosphere Reserve. It is usually likened to Surprise Cave (Hang Sửng Sốt). They are both spacious and have stunning limestone structure except that Dark and Bright Cave is a sea cave which mostly is under water.
The cave is unique for its brilliant light glow which comes from its two ends. When viewed from inside the cave, the entrance appears as a brilliant picture frame just above the water line.
Not many attractions are blessed with such a stunning beauty and diverse ecosystem. It rightfully deserves as a an inevitable part of the Heritage Site.
Inside the cave, the lake is surrounded by mountains. On the cliff one still find traces of fossils of fresh-water snails, which prove that men used to live there and this must have been a deep valley before. Stop your paddles, enjoy the majestic scenary and listen to your breath, feel the connection with nature. Indulge yourself in the serenity of the nature that is missed out for all the time you stuck in the hustle and bustle life of big cities!