Close to two thousand limestone islands rising straight out of green water, and the photos don’t do it justice. The day boats head back to port in the afternoon. Stay out overnight and you get what comes after: kayaking between the islands at sunset, a quiet deck, and mist on the water when you wake up. Lan Hạ Bay, next door, has the same scenery with fewer boats and small beaches.
The bay’s biggest cave, huge chambers on Bồ Hòn island.
Climb the steps for the classic panorama, then swim at the beach below.
Kayak or bamboo boat through a low tunnel into a lagoon ringed by cliffs.
Two rocks facing each other: the bay’s most famous outline.
The day boats are gone and the islands turn into silhouettes.
Quieter water next to Cát Bà island. The best kayaking.
A day trip shows you the scenery and gets you back the same night. It’s a long day, most of it on the road there and back.
Three days takes you further from the other boats, into Lan Hạ or Bái Tử Long, with more kayaking and a slower pace.