Route notes
Why this routing works
This routing uses an open-jaw structure in Southeast Asia: fly from New York City into Siem Reap, continue overland to Hanoi, then resume flying south to Ho Chi Minh City before the long-haul return to New York City. That setup works well for travelers who want to cover Cambodia and Vietnam in one ticket without backtracking to the same city for both arrival and departure.
With 7 nights in Siem Reap and a total trip length of 4 weeks, the schedule leaves room to distribute the remaining time across Vietnam while keeping the overall route straightforward. The overland Siem Reap-Hanoi segment is the key planning choice here, since it breaks the trip into a surface sector rather than requiring every leg to be flown on one continuous ticket.
In economy class, this itinerary sits in the USD 1,478 to USD 2,255 range based on the provided trip data. A November departure falls within the October-December season window, which is useful for timing a transpacific outbound and return around a single four-week trip frame.