North to south, or south to north, and what the choice costs

Vietnam is a line, not a circle. The country runs about 1,650 km end to end and narrows to roughly 50 km across in the middle. A trip that covers it goes one way or the other and flies home from the far end.

Which way is a real question with a boring answer: the calendar decides it, not the map.

Which direction should you pick?

The one that puts the dry end first. Vietnam holds three climates on that line and they rarely agree, so the direction that works in March is the wrong one in November. The month-by-month guide has the full picture; this page is what it means for the order of a route.

Why does the north come last in winter?

Because a first impression of Vietnam should not be drizzle at 16°C. From December to February Hanoi sits at roughly 15 to 20°C, under grey skies and a fine rain that never quite stops. Ha Long in those months is sailed in a mist that hides the limestone.

None of that ruins a trip. It ruins a first week, when jet lag and a new country are already doing enough. Ho Chi Minh City is warm and dry in those months, so starting there and arriving north later hands the cold weather to a traveller already at home in the country.

Why does the north come first in summer?

Because the mountains are at their best and the south is not. From May to August the northern valleys are green, the terraces are flooded or growing, and the trekking works. The south is hot and takes a heavy afternoon downpour most days.

Southern downpours are predictable and short, which makes them easier to absorb at the end of a trip when the plans are looser. The rice terraces guide covers the two windows that make northern timing worth planning around at all.

What about the central coast?

The central coast disagrees with both ends, and it is why September to November is awkward in either direction. Hue, Da Nang and Hoi An take their rain from about September to December, with the worst of it in October and November, and Hoi An floods in a normal year. From the capital, the Hanoi to Hoi An guide compares the flight, the train and the bus.

If your dates fall in that window, plan the middle of the country loosely and give the days to the ends. The five-day central route is worth compressing rather than cancelling.

Does the direction change what it costs?

Almost nothing. The same flights, trains and sleeper buses run both ways at the same prices, and both ends have international airports.

The one saving is the ticket shape. An open-jaw fare into one end and out of the other avoids the internal leg back to where you started, which in a country 1,650 km long is either two hours in the air or 32 to 35 hours on the train. The transport guide covers when each mode is worth it.

How long does the whole line take?

Two weeks as a minimum and three to do it without living in transit. The two-week route is the compressed version: three bases and one internal flight. The three-week route is where the second half of the country stops being a blur.

Anything under ten days should pick one end rather than run the line, which the ten-day route sets out in detail. Vietnam is long enough that half the country is a full trip.

Is there a wrong direction?

Only one, and it is a season rather than a compass point: starting in the north in January and expecting the photographs. Everything else is a preference.

The railway is the tie-breaker for some people, because riding one overnight leg is better going north to south for the coastal stretch between Hue and Da Nang in the morning light. The train guide covers which legs repay the hours and which to fly instead.