It’s true domestic flights within Vietnam are relatively inexpensive and quick, but there is much more to see between the two main cities of Hanoi and Ho Chi Minh City (the former Saigon).
Trains in Vietnam are coded, and it’s helpful to know what you’ll be getting on a certain timetable. There are several types of Vietnam trains. We booked SE trains, which are billed as a bit more modern and faster.
The SE 1 and 3 trains supposedly make fewer stops than SE 5 and 7. Air temperature was relatively comfortable on each of the Vietnam trains we took, and food and other refreshments were served at your seat and/or in a restaurant car.
Pay attention to the types of seats offered: hard seat = nothing more than a wooden bench, Vietnam train soft seat = individual cushioned seats, hard sleeper = 6 berths per compartment, soft sleeper = 4 berths per compartment.