What are some unusual facts on Vietnam?

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I have to do a project on Vietnam and I need some unusual facts

Travel Tips

You have gotten some pretty good answers so far, but nothing really unusual to my standards (sorry Ong Jon, I have to one up you on this question). Then again, I've been studying Vietnam for a long time, and I know a few more things than even many of the native Vietnamese may know.

Here are some unusual facts that you may find hard to find:

Vietnam has one the longest free flowing subterranean river in the world at Phong Nha - Ke Bang. The river flows through a huge cave or "grotto." It is not known how far back the grotto goes (easily a couple miles) or how deep the water is in the grotto. This was also one of the largest North Vietnamese military bases during the Vietnam War and the major starting point of the Ho Chi Minh Trail. The grotto is so big that you can literally fit a small city in side it.

Hoan Kiem District of Hanoi has their business district designated with streets specializing in one kind of product or service. i.e. You buy shoes on the "Shoe Street", Shirts on "Shirt Street", etc. This has been so for hundreds of years.

Halong Bay contains 1,969 limestone islands, and many have grottos in them. It is not known how many grottos there are in the islands of Halong bay or in all of Vietnam. It's argued that Vietnam has more grottos than any place in the world. It is not known how deep most of these grottos go, due to the lack of technology to find out and the sheer number of them.

What you will not read in the tour brochure of the famous Cu Chi Tunnels are the hundreds of bomb craters that ravage the area. Twenty foot wide by six to teen feet deep bomb craters are found everywhere in and around the Cu Chi area. Cu Chi was a major Viet Cong stronghold but is now within the city limits of Ho Chi Minh City. You can take a city bus to visit it.

Vietnam repelled three Mongol invasions and was one of the few Asian societies not influenced by the Mongolians (the Japanese were another one). China was conquered by the Mongols during the same time. This is one of many reasons why the Vietnamese are distinctly different from the Chinese.

Hanoi is protected from the Red River by a levee. The levee has been in place for hundreds of years. Most of Hanoi would be under 10'-15' of water if the levee were to break during their rainy season. Such a disaster would make New Orleans look like a bad thunderstorm, because Hanoi is home to more than 6,000,000 people with no realistic means to evacuate most of the population if such would happen.

The Vietnamese conquered the Cham empire, who controlled much of South Vietnam before their defeat.

The Viet Cong controlled the jungle area South of the Saigon River during the Vietnam War. Much of that area is now being developed into high rise condo buildings and residential housing and bought mostly by the Vietnamese who had fled from the country after the War ended.

Feel free to ask me if you want to know more... Source(s): Studied Vietnam and Vietnamese history for many years.
Other Travel Tips

agent orange (a chemical used during war with the US) still affects its citizens. look it up on wikipedia, the images are disturbing
It was at war with China, after the US left.
Although it is considered to be a "third world" country (or developing nation), Vietnam is the only nation to have defeated the most powerful nation in the world, the United States. I think that's interesting and noteworthy.
Erm.... Well... Education In VN has many negativations.... 8-} It's a big secret can be known by a little pupil like me :-"
well, ive always found it curious that although the french tried to enslave them, and the americans covered them w/ napalm and agent orange, the vietnamese not only forgive both but truly embrace their french heritage and just love americans.. they are quite "centered "people.
i also have seen that from the individual level to the nation as a whole they find no task insurmountable... they take for granted they can do anything... and they always do..