Getting to Halong Bay is simple, and most travellers choose to do so from Hanoi, a mere 3 and a half hours by bus or faster still by private car.

Overland
There are many 'open tour' buses that will bundle a trip to Ha Long bay with a cruise on the water - these vary in quality from basic to luxury but generally if you are booking a cruise then transport will be paid for.

A private car or minibus will set you back between $80 - 120 one way and will be one of the fastest ways to cover the 170 km to Halong city as you will avoid unnessecary stops.