How to search for a flight when dates and cities are flexible but non-direct flights must not pass through a particular country?

Question

Sometimes when booking a trip you can be very flexible with many factors but any route passing through a certain country cannot be considered.

Say you're going from country A to country B either direct or not, but if not direct must not be via country C. But any city in any airport in both countries is fine, especially when the ticket is cheaper and you don't have a specific itinerary.

For instance if you're from a country where you would need a visa even to pass through one other country who has some of the common hubs between your origin and destination. Say if that country's visa is difficult to obtain given your nationality or something like overstaying in the past, or just having strict requirements you couldn't easily meet. Like if you're from a poor country going to another poor country but an intermediate rich country needs you to prove your finances, employment, etc that your destination is not too bothered with.

I'm not aware of a flight search engine which lets you specify a country or countries not to pass through along the way.

Is there a search engine I don't know about that has this feature? If not, is there another way to search for flights given this constraint using the usual flight search engines along with some trick or method that might not be totally obvious?

Answer 1

Yes, the ITA Matrix supports the undocumented l: syntax in the routing specifier to search by location. You can use l:nXX to search by ISO country code (n for nation), and then add the negation symbol ~ to invert this. Putting it altogether you want ~l:nUS* to mean, possibly transit at any number of points, but none in the United States.

See this thread on FlyerTalk for a little more information.

Answer 2

Kayak.com also offers this exact functionality. To search for flight route from A to B, but not transiting through X/Y/Z,

• Search flight as usual.
• Once you are on results page, there are search filters on left of the page.
• Find the filter labeled as Layover Airports (Click more filters if required), and deselect the layover airports you do not want. Good thing is all these layover airports are also grouped by Country. (means all airports in America will be in one group, & etc etc.)
• Uncheck all the airports you do not want to transit through.
• .....
• Profit!!

Some Reasons why this might require:

• USA/Canada treats anybody with Indian Passport asking for transit visa against the same requirements as standard tourist visa. Many flights from Delhi to Trinidad/Panama transits in Canada/US.
• Indian Passport holders, going from non-schengen to non-schengen, but transiting at AMS does not need Holland transit visa, but transiting through CDG needs French transit visa. E.G. Delhi to Panama flights always transit at either/or LHR/AMS/CDG, only AMS allows TVOW (transit Without a Visa, to Holders of Onward Tickets), whereas France/UK does not (some exceptions: Holders of Visa/residency of US/Canada/UK/Ireland etc), .
• If one takes a loan in Gulf Countries, & does not pay it back, & run away; then any time in future he transits through one of the gulf airports, much likely chance is that one will be arrested & prosecuted for that crime.

Edit:

Reader advised to not default on loans (and then run away) on any country, not only [assumed persian] Gulf. (Thanks to Mindwin's comment)