Route notes
Why this routing works
This is a compact one-week multi-stop itinerary that starts and ends in Tokyo, using a simple loop through Hanoi, Vientiane, and Phnom Penh. With just 1 night in Hanoi, 2 nights in Vientiane, and 4 nights in Phnom Penh, the schedule is weighted toward a longer final stop before the return to Japan.
From a ticketing standpoint, this works as a focused regional routing rather than a longer round-the-world structure. Keeping the trip in economy and within a single week makes the connection order important: the shortest stay comes first, followed by a slightly longer middle stop, then the longest stay at the end before closing the itinerary in Tokyo.
June timing places this trip in the apr-jun season window provided, which suits a fast sequence of flights where each stop has a defined role in the overall schedule. For planning purposes, the route is straightforward: depart Tokyo, move south through mainland Southeast Asia, and return to the same origin city without adding extra backtracking.