Halong Bay, where the dragon is hidden, a sight for the eyes and a rest for the soul.
We arrived through a tourist pack from the same capital of Hanoi. It is really difficult to make the trip on your own, so it is best to walk around the city and trade the best price. We discovered that in the end, whether it's a high or low budget, they end up putting all the tourists in the same boat. We were lucky and went for the cheap price and once in Halong Bay they put us in the same boat that others had paid for a much higher price. The only difference we saw is in the accommodation for one or two nights.
The cheapest thing is to sleep in a hotel on the island of Cat Ba, while spending the night on the boat is more expensive for romantic but not precisely for comfortable according to what some tourists told us with whom we agreed to return.