Part of the 5 Star experience included an overnight tour of Ha Long Bay, which is an Unesco World Heritage Site.
One of the reasons that truly sold this tour for us!
"Ha Long" means descending Dragon 

Ha Long Bay is in the gulf of Tonkin, North East of Hanoi and includes over 1600 islands
& islets made up of limestone pillars.
According to the Unesco. org website "most of the area is unaffected by a human presence"
however the boat cruise lanes were littered with garbage, which I found very depressing.
Our boat crew was fishing bottles and other recyclables out of the water and then some 'idiot' would
throw another one over board

This boat was very similar to the one that we were on.
Although ours did have the traditional "Junk" sails