Flights from/to ATL

The fastest routings can be found at www.Skyscanner.com. It is usually less expensive to first fly into major cities such as Frankfurt, Munich, Milan, Rome, Naples., Paris and Amsterdam and then fly direct on to Dubrovnik. Since Atlanta is a Delta hub, and Delta partners with KLM and Air France, you might focus on “multi-city” tickets with those airlines.

Have you tried putting your itinerary in under a multi-city trip on either the Delta site or in one of the search engines? Sometimes they will return reasonable options and you can compare that with a round-trip to a major city plus the two one-way flights.

Your definition of best would be helpful here.....

I think the only way you could financially improve on what Kenko and Jimbo
(sorry, that just sounds funny) are advising would be to fly to a gateway city and
then fly some low-cost carrier(s) as 1-way trips to/from DBV and SPU. But then
you have to pad the schedule to allow for missed or delayed connections,
and maybe add in the cost of a hotel room for a night either way. So it could be a wash.

A one-way to a destination with a return from a different city back to the same
origination city is called an "open-jaw" trip, and you should definitely purchase
it that way vs 2 independent 1-ways, as the fare rules are very unforgiving on
1-way trips. It is another term for "multicity", but multicity can involve more than
3 cities.

Zagreb is the Croatian city with the most flights, but it is a bit of a hike to Split
and especially to Dubrovnik. Train service in Croatia is pretty ancient, so you
would probably rely on buses.

Agree with above on multi-city. So, in multicity mode, your hometown to Dubrovnik and the Split to your hometown. Skyscanner to look at all the options. Delta, if you are a Delta guy (I am).

One exception may be looking at multi city from JFK. Very competitive market for international flights to Europe and can get a round trip from hometown to it. I have done that a few times to save money. Just leave plenty of time to make the transfer and beware that on the odd chance you miss the JFK flight, you would be buying a full price ticket. So there is risk with that strategy.

Thanks, everyone. I actually found one-way tickets on Delta (and Air France) from ATL to DBV, then Split to ATL. The total for 2 was about $500 less than for "multi-city" going from ATL to DBV, then Split to ATL. I appreciate your knowledge!