Route notes
Why this routing works
This round-the-world itinerary runs east from Lisbon through Southern Europe and onward into Asia before crossing to Australia. Keeping Rome and Istanbul ahead of the longer intercontinental sectors breaks the trip into shorter stages before the move to Bangkok and Singapore.
The Australia section is handled as two separate stops, with Sydney followed by Melbourne, before the routing continues north to Tokyo. That sequencing keeps both Australian cities on the same ticket rather than requiring a backtrack later in the trip.
With four weeks total in economy, the plan spreads the longest flights across a steady progression of hubs rather than concentrating them at the beginning or end. The final Tokyo-to-Lisbon leg closes the loop cleanly, making this a true round-the-world ticket rather than an open-jaw itinerary.