Anyone been there before??
Would like to visit its place once had collected enuf info..
preferably , info from the people who have actually been there...
anyone? anyone? 
Halong Bay in Vietnam.
Absolutely worth a visit! Is an amazing place. When I was there in July 2002 we swam in the Bay (off a boat, not from the beach), but a friend whoreturned recently said that they were strongly advised against swimming and so were unable to have such an amazing opportunity!
Regardless, it's a great place to go, and was beautiful in July when I was there - I've heard it's not so good around Feb (which is when I'm heading there next, so I'll let you know!).
I hope you decide to go, as the scenery is great, and I'm sure you won't regret it.
Hi Hayanna, 
Tours to Halong Bay can be arranged in Hanoi. The bus, meals, boat trip, hotel accommodation, and a cave tour was all included. Well worthwhile.
You may care to also catch a train up to Sapa in the north east of Vietnam, close to the Chinese border. Some lovely mountains and ethnic groups.
Forgot to mention that I was there in late December. Take an umbrella or raincoat with you. 