Tin tức Blogs Introduction about Luon Cave or Luon Grotto! 12/05/2016 Luon Cave is about 60 meters long and 4 meters wide. Height of the ceiling ranges from 2.5 – 4 meters up on tidal level. Therefore, it only can be accessed by small boat or kayak. Luon Cave- Luon Grotto on Halong bay tours! Passing through Luon Cave, tourists will reach a lake formed by an enclosed group of lime-stone mountains. The lake inside seems like a stadium surrounded by high podium. It’s a brackish lake with calm and green sea water. Size of the lake is nearly 1 square kilometers. On the cliff are many fossilized freshwater snail shells proving that place used to be a deep freshwater valley. Especially, it’s highlighted with pristine setting of ferns, orchids and wild golden monkeys. The perfect combination of lime-stone mountains and jade-green sea makes Luon Cave a unique site to visit on Halong bay. Furthermore, Luon Cave is a preferred place of tourists for kayaking.