Zagreb: Worth a couple of days, no more.
The upper town (which is the old town) is charming and the lower town has some seriously civic buildings and museums and parks. In between the old and new towns is the daily market- fabulous!
Favorite: The Museum of Broken Relationships.
Plitvice Lakes: an intagrammers' paradise! You can see it all in a day. Walk all the way to the top lake and then you can get a bus back to the gate - or vice versa.
It is very crowded - best tip, stay nearby and visit first thing in the morning.
Krka National Park: Spend a day here or visit as we did on our way from Zadar to Split. Nice walking tracks along streams ans past waterfalls. Same but different to Plitvice.
Zadar: A day or 2. A pleasant coastal town, not as touristy as some.
Best bits: the sea organ and the monument to the sun.
Split: Spend several days here. So much to see and do!
Wander the lanes of the Diocletan's Palace; walk, drive or ride a bike to Marjan Hill - a parkland with a view.
From Split you can take boat trips to access the islands - Hvar being a popular destination.
There are also car ferries to some of the islands and it may be possible to island hop that way.
Best bits: Hvar at the end of the tourist season
The drive along the coast from Split to Dubrovnik is stunning! although it is quite well-populated with holiday accommodation. You have to briefly pass through Bosnia and Herzegovina along the way.
Dubrovnik: It may be over-exposed but it is beautiful. If you stay in the old town, or nearby, you can get to the sights before the cruise tourists arrive and then you have the evenings and nights as well.
Walk the walls, catch the gondola up to the Imperial Fort overlooking the city and walk back down, cruise around the closest islands stopping off along the way, sunset kayak in the bay.
Best bits: Appreciating how Dubrovnik suffered in the Balkans war.
Pst: Dubrovnik isn't that far from the beautiful Bay of Kotor in Montenegro. You've come this far you might as well tack that on as well. You won't regret it.
Stay in Kotor town, climb up to the fortress, take a boat trip on the bay, swim in the blue cave.
How we travelled: We flew into Zagreb, hired a car and drove to Split via Plitvice, Zadar and Krka (not all in the one day!)
Picked up another car to leave Split (you won't need a car when you are in Split) and drove along the coast to Dubrovnik. If we'd had more time I'd have investigated the possibility of car ferries between the islands to get from Split to Dubrovnik.
Left the car in Dubrovnik and took a bus to Kotor as multi-country car didn't work for us as we were through-travelling. It may be possible to drive to Kotor and then back to Dubrovnik to leave the hire
car.
*This is by no means an exhaustive tour guide to Croatia, it's just where we went in the time we had.
