One month in Vietnam [closed]

In a tight schedule, it's possible to do Hanoi + Ho Chi Minh within a week, spending two day at both cities. Trains between the two cities is an overnight journey, and it's also possible to travel by bus with breaks at (most commonly) Hoi An / Hue / Da Nang (and sometimes additionally Da Lat). Anyway, so my point was that it's certainly doable-if-rushed in a week, and a month gives you more than enough to enjoy the sights slowly and take it all in. Rent a bicycle or a motorbike if you can and make your own way, like the Vietnamese, although the traffic is a bit insane within the cities.

I'd recommend spending a long time in Ha Long Bay. Of all the places that I have been to, that is by far the best. You can spend weeks there and not want to leave.

As for when. I never got to do this, but I'd recommend visiting during the Tet festivities. It's at a different time every year, so check up when it is for whichever year you want to go - usually around January - March. This ties in nicely with the period when it typically isn't too hot, although towards March you'll get more rain as it nears monsoon season.

As @choster stated in the comments, you better 'immerse' yourself with Vietnam information provided in the (excellent) travel guides available. (in my experience, Lonely Planet is very thorough)

About your two questions, they are interconnected. It also really depends on what you want. Climates in the northern, middle and southern regions differ from each other. However, it seems that the best time to go lies between november and march, no matter where you are.

You can make it from north to south in a month. However, also here the big question is what you want to do / see. Vietnam has fantastic cities north and south, great national parks, and a diverse, rich culture.

Check here for some more detailed information about climate conditions. I also suggest reading travel blogs like this one.

I've been to Hanoi in August and March. August was almost insufferably hot and humid. I rained everyday and tropical depression also came through (the streets flooded). March was much, much more pleasant. Completely comfortable.

I was also in Ho Chi Minh City (HCMC) in March. At about 800 miles South of Hanoi, it was considerably warmer.

I would not consider avoiding rain to be a goal in SE Asia. It would be better to just expect it to happen. Nicer hotels will have umbrellas available. Umbrellas or ponchos can be bought locally for a pittance.

You can make it from Hanoi to HCMC easily on a discount airline. Seeing all of Vietnam in a month it completely reasonable.

Feb to april is the best time to visit Viet Nam. At that time, no need to worry about the weather condition, and you can join in Tet Holiday. If you can, get to Hoi An on Tet holiday as you can see the true local event.

I also did a trip from the north to the south, it's possible. To the north, you should start your trip in Ha Noi (2 days), Sapa (2 days), Ha Long bay( 2 days), if you have time, take a tour to Ninh Binh.

Then make your way to the central part as Hoi An (3 days) , Hue (1 day), Da Nang (1 day).

In the south, Ho Chi Minh (2 days), Mekong delta (3 days).

In fact, it depends on your time and budget.