A stunningly beautiful bay filled with thousands of tall, sheer limestone islands topped with tropical rain forests. The bay is a UNESCO heritage site and one of Vietnam’s most popular tourist attractions for a reason. Most people spend a night or more on a boat on the bay, and we highly recommend it. It’s possible to see the bay on a day trip from Hanoi, but it’ll involve a lot of driving, and you won’t get to see as much of the bay. However your arrange your trip, you should be sure to see the Amazing Cave and Ti Top Island.