I am planning a trip with my parents and my wife in August to Slovenia and Croatia. I will begin my journey from Freiburg im Breisgau in Germany. In Slovenia I intend to visit Ljubljana, Lake Bled and Postojna Cave. In Croatia I would like to see Plitvice lakes and Zagreb.
I plan to spend 3 days in each country. From there, I will be proceeding to Vienna. It costs me the same to reach Zagreb and Ljubljana from Freiburg. Initially I was thinking I will do:
Freiburg → Ljubljana → Bled → Postojna → Ljubljana → Zagreb → Plitvice → Zagreb → Vienna.
But in this itinerary I would have to visit both Ljubljana and Zagreb twice. I would like to know if there is any way I can rearrange the trips such that I don't have to pass through the same place twice. One constraint: I have to start from Freiburg and proceed to Vienna; I have no other restrictions. How can I plan this trip best such that I can save on time and money?