Halong is one of the World Natural Heritage, which explains the fascination of tourists everywhere to come visit Halong. Being 170km away from Hanoi capital, Halong Bay is easily accessible.
If you are travelling on your own and want to save cost, taking the bus from Hanoi to Halong can be a good thrill. From Kim Ma bus station on Nguyen Thai Hoc Street, you can take Hoang Long express which departs every 15 minutes from the station. It will take about 3-4 hours to reach the pier. The cost is about 60 000 VND. After that, there are plenty of cruise operators that you can choose from to hop on. This way of transport is exciting partly because you get to be part of the daily commune of the locals, who come and go to Hanoi. Additionally, with someone who has no fix schedule, taking the bus is very convenient. However, this type is more suitable for those who are more familiar with Vietnam conditions or has adventurous streak; for first time tourists, it is not recommended.
Of course, the most popular way to go from Hanoi to Halong Bay is to book a tour. Tours from operators are cheap and available every day. They will take care of your transportation, cruise and accommodation. There will also be a guide that will help explain things along the way. Depending on the different tours operators, all of them will provide shuttle bus that starts from the Old Quarter. Some will also have private car option for you if you do not want to join 20 others on a shuttle bus. This will increase the cost but also comfort. Going on tours is recommended for family, group of friends and anybody who want to have a fuss free trip. An average cost for a 2 days tour is about 3 million VND. The operators will take care of everything. To book a tour operators, you can scout around the old quarters, there are plenty of choices depending on your budget and types of add ons.
Once you are in Vietnam, you can reach basically everywhere by motor cycle, even at the most remote places. This type is the utmost adventurous and thrilling of all. Since Halong bay is only 170 km away from Hanoi and the road is quite straight forward, one can rent a good bike from the Old quarter, a map and good riding skill to make the trip. It is advisable that you should embark on this with a small group of friends to support each other on the way, especially in case a bike brakes down. Careful inspection of bike before the trip is crucial to ensure a safest trip. An average price for bike rental is about $20/day. However, it will take slightly longer than bus or car to reach Halong and is considerably more tiring. Thus unless you plan to stay long in the area, riding the bike to Halong is not very worth it.