A coherent sequence
- Days 1–2: Hanoi arrival, heritage and food.
- Day 3: Ha Long Bay with the exact cruise and transfer format checked.
- Day 4: transfer and fly to Da Nang; continue to Hoi An.
- Day 5: Hoi An at a slower pace.
- Day 6: fly Da Nang to Ho Chi Minh City.
- Day 7: one Ho Chi Minh City anchor plus flexible evening.
- Day 8: fly home from Ho Chi Minh City.
Where this route can fail
- A same-day Ha Long return and domestic flight without sufficient disruption buffer.
- Separate international tickets that require backtracking to Hanoi.
- Domestic baggage or terminal assumptions copied from an international ticket.
- A late-year Hoi An plan with no rain-safe alternative.
The slower alternative
Remove southern Vietnam and use the extra time for Hanoi, Ninh Binh, Ha Long and Hoi An; or remove the north and combine Hoi An with Ho Chi Minh City and the Mekong. A highlights route is a sampling strategy, not the default best answer.
Quick answers
Are eight days enough for north, central and south Vietnam?
Enough for a first sample, not for depth. The route works only when flight timings and open-jaw geography protect usable time.
Should I add Ninh Binh to this route?
Only by replacing another anchor or extending the trip. Adding it on top of Ha Long, Hoi An and Ho Chi Minh City would make the route more fragile.