Bai Tu Long Bay is one of those beautiful places which you can enjoy to the fullest and at the same time there are almost no tourists to interfere with your experience.
There are many cruises that you can choose from, but most take about 45 minutes till you can see the islands and enjoy their beauty. They are said to have one of the best beaches in Northern Vietnam. It's also a home to one of Vietnam's national parks, Bai Tu Long National Park, which reaches from land to water.
It's also a protected area, so boats cannot anchor there overnight.
Wikipedia https://en.wikipedia.org/wiki/Bai_Tu_Long_Bay
Coordinates 20°55'33.832" N 107°15'18.755" E
