Vietnam is very interesting, to say the least. It is a beautiful and bountiful country; its people are colourful; its cities, busy; its food, divine. It is an Asian country like no other.
Saigon or Ho Chi Minh City is a place that proved too much. It's overly busy and over-populated, among other things by, motorbikes. To cross Saigon roads on foot is, literally, to put one's life on the line. Pedestrian crossings hardly exist and where they do, motorists would just as likely drive around and about pedestrians once the red light turns green (which doesn't take long), seemingly hell-bent on where they're going, pedestrians or not. Hoi An's pace and ambience was more to my temperament and Hanoi was charming and quaint.
I travelled by train from Ho Chi Minh City to Hoi An and further on to Hanoi. It was a long trip that divested me of at least two days. Flying, on the other hand, between Ho Chi Minh City and Hanoi takes all of an hour and a half and is not a hard choice to make over other options. One can fly and still make stops in-between large cities. Ignore romantic notions of travelling by sleeper train in Vietnam; first-class cabins are anything but.
Halong Bay is gorgeous and time in a junk boat on Halong Bay is highly recommended. Advisable though, is to choose the company to book it with. I booked from Australia and although it turned out to be legitimate, the junk boat left a lot to be desired. It was cold and raining; heating didn't work, water dripped onto the bed in the cabin and extra blankets were not available. If you're stuck out in the bay in such weather, there's no other option but to wait until the morning to get warm.

Apart from the beautiful sights, what I also loved in Vietnam was the food. Vietnamese food is a unique cuisine with distinct Chinese, Thai, Laotian, and Cambodian influences. It has a flavour and aroma all of its own. It is an amalgam of the five taste elements (bitter, sweet, sour, spicy, and salty) and every Vietnamese dish has a distinctive flavour that contains one or more of these elements. It's one of the world's healthiest cuisines; it uses a lot of fresh ingredients, is essentially dependent on fresh herbs and vegetables and uses only the smallest amount of oil. Lemongrass, Vietnamese mint, long coriander, Saigon cinnamon, bird's eye chili, lime and basil leaves are some of the ambrosial and delicious herbs that contribute to the beneficial, yin-yang balance effect to the body of Vietnamese cuisine.

Ho Chi Minh City has markets, temples and museums a-plenty. If you're after shopping, this Vietnamese city is good for it. If you like to get to know the Vietnamese culture better, then this city is recommendable for its museum displays from ancient Vietnam, to the Chinese dynasties governance eras, to Indianised civilisations in the north, to the coming of the Europeans, to civil wars, and to the Vietnam War. Buddhist, Chinese and Hindu temples and pagodas outnumber museums in the city and are among the top tourist attractions.
Hoi An also offers an abundance of shopping. Here, you can visit a tailor's shop and have a couple of suits or dresses made in an hour or two. It is perfect for a few days' stay. I had my measurements taken on the day I arrived and my new Vietnamese silk dresses were ready the next day.
It was rainy and cold in Hanoi. I travelled in spring when it was also the wet season. Luckily for me, I only stayed for a couple of days. Hanoi has a charming mixture of French and traditional Vietnamese architecture. It's a logical base for a Halong Bay trip; a hundred and seventy kilometres west of Halong Bay or a three-hour drive to Halong or back.
Flights from Brisbane to most Vietnamese cities take around eight hours. Jetstar operates domestically in Vietnam and flies between seven cities. Vietnam Air and other regional airlines can can also take passengers to and from other destinations and nearby countries, such as, Cambodia, Laos and Thailand.