Croatia/Slovenia Trip

Full disclosure: we have not been to either Vis or Rovinj, so I can not comment on those. But in looking at your plan my comments are:
At what point in the trip do you plan to rent a car? Have you thought about parking? If you rent a car in Croatia and drop it off in Slovenia, you will incur a large drop off fee. Have you taken that into account for your travel budget?

Two nights equals one full day, so not a lot of time to explore and enjoy a destination. You need to think about packing up, traveling to a new location and settling in there. Look at your travel time from Vis to Plitvice and from there to Rovinj. Plitvice is packed with day trippers, so unless you are there first thing in the morning, or very late in the afternoon it will be a madhouse. What is the attraction to Vis?

You say 3-4 nights in "Slovenia". Which locations in Slovenia are of interest to you?

I understand the feeling of not wanting to miss out on something, but I would suggest you think about which places are most important, and then reconfigure your travel plans. If you come back to the forum with an updated plan, you may receive more suggestions.

We’re talking broad strokes at this point, but I have a few thoughts. Add at least one night to Dubrovnik. This trip is a marathon, not a sprint. An extra night or two to get settled makes sense. There’s also a lot of day trip options, hiking and kayaking you can do. It’s worth looking at.

Based on your stated interests, I think you need more time in Slovenia. Ljubljana itself deserves a few days, but then there’s tons of activities besides. Lake Bled, Lake Bohinj, the caves, and the Julian Alps could be a whole trip on its own. I think the easy sacrifice here is Rovinj and Istria. Rovinj is generally similar to Korcula (both Venetian-era port towns) and will offer similar experiences. So, you have some sightseeing overlap here. The feedback I’ve seen on this forum regarding Istria is not particularly enthusiastic, and the other towns like Pula don’t seem to impress on the whole. If you really wanted to get up this way, Piran would make sense as part of your Slovenia leg.

Is there a particular reason you picked Vis? With just a few days, I feel like adding some more time to Korcula and/or adding Hvar would be just as good. It’s a little more convenient and both places offer plenty of activities.

You might also look into Mljet, which is a big national park island between Dubrovnik and Korcula. Stopping here or day tripping from Korcula via public ferry can be complicated. But based on your interest an overnight might be worthwhile.

Thank you for the suggestions and thoughts- I think I will not go to Rovinj area and perhaps not go to Vis.

I may post a new itinerary. As far as renting a car- I am not sure- perhaps I would rent the car AFTER Dubrovnik- when I leave Dubrovnik and bring the car to Zagreb and then get to Slovenia without renting a car and then rent on in Slovenia. Does that sound like a better plan?

You won’t need the car until you leave Split/the coast. The ferry service is easy, scenic and inexpensive. Once you’re heading to Plitvice you can consider the car. Where this gets complicated is there are typically extra fees for dropping the car in another country (Slovenia.) So, you might consider a car for Plitvice, dropping it in Zagreb and then taking the bus to Ljubljana and maybe rent another car there. Or you just eat the fees in favor of the convenience and drive straight to Slovenia.

When I've checked the dropoff fee for a rental car picked up in Zagreb and dropped off in Ljubljana, it actually wasn't that bad. That was 4 or 5 years ago, but I was pleasantly surprised at that time that the commonly encountered high dropoff fee was not the case.

llyynnee,
Regarding the rental car, we did exactly what you are proposing. We picked up our rental car the morning we left Dubrovnik. We dropped off our rental car the day we arrived in Zagreb. We spent 2 nights in Zagreb, and then we took the train to Ljubljana. Very easy.

We spent 3 nights in Ljubljana. We rented a car for a day to drive to Lake Bled for the day. And returned to Ljubljana.

I agree with the advice to spend 3 nights in Dubrovnik. It gives you time to get over jetlag. And if you care to do so, you can take a daytrip from Dubrovnik. We hired a private driver to drive us around the Bay of Kotor, and we made stops in Budva, Kotor, and Perast.

llyynnee -

I had almost the exact "sketch" of an itinerary to Croatia & Slovenia but need to cut out some spots and narrow it down to a week to 10 days end of June. Let me know what you ended up with for an itinerary! I've heard Vis is wonderful to see and my friend loved it.

I prefer trains but know that Croatia doesn't really lend itself to that as well as some countries. But, not super excited about renting a car as I'm solo.

D

In October 2013 we traveled in Croatia & Slovenia by car for 3+ weeks. We made reservations only for Zagreb (3 nights) after our USA flight and in Dobrovnik before our to Venice flight. This is normal for us to make sure we are ready(?) for any flight problems. Rented the car in Zagreb, traveled to Ljubljiana (3 nights). Took mostly back roads to Lake Bled (2 nights). Vintgar Gorge is enchanting. Over the Julian Alps to Soca Valley. Lovely drive with interesting history. Stayed in Kobarid, visting the museum & mausoleum. Stopped (Divaca) near Skocjan Caves and visited them the next day. Thru Piran (lunch & shopping), across border (no problems) to Rovinj (3 nights) with a day trip to Pula. We loved the small, medieval with good seafood Rovinj. Next to Plitvice Lakes (1 night nearby). Not to be missed in spite of crowds! Then down the coast: Zadar, Split, small towns. Stopping when dark and usually finding good restaurant advice from our hosts. Ferry from Drvnek to Hvar Island and a narrow road to Hvar town. 3 nights with some short drives to sites but mostly walking town and fort. Back to ferry & mainland coast road to Dubrovnik. Turned car in - stayed Dubrovnik 4 nights. The host's nephew as taxi to airport. Parking was a problem only in Split. Roads were good if narrow. Signage was good. Other drivers were aggressive but usually skilled and forgiving of goofs. There were times when we had to use the new high speed highways and they were very good. The people were initially reserved but polite - opened up to us when we showed interest in their activities, history, etc.

Hello from Croatia, I’m local person and definitely you don’t need car until you start journey from Split to Plitvice. One of the option is private transfer from Split to Plitvice and then to Ljubljana. Can be just stop or overnight.
This part of journey from Dubrovnik to Split with island is fine by ferry.
If you need help with private transfer or some other question you can DM me.

Thanks to everyone who responded!
I have come up with this as my "mostly" final itinerary-
Dubrovnik- 3 nights
Korcula- 2 nights
Split- 4 nights- many day trips- Trogir, Omis
Vis- 3 nights
Plitvice Lakes Park- 1 night
This is where I'm stuck- I HAVE TWO NIGHTS-NOT PLANNED YET- Not sure if I should do Zadar or Rovinj or even somewhere else I haven't thought of
Ljubljana- 5 nights

Thoughts?

@Larry42 Do you mind sharing where you stayed in Kobarid? That's one piece of my Slovenia trip I haven't gotten accommodations yet. Thanks!

llyynnee:: When we visited Croatia & Slovenia 10 years ago, we made reservations in Zagreb, Dubrovnik & Ljubljana, but no where else. Can't remember the name - pizzeria ground floor and rooms upstairs (accessed via stairway in the rear from a small parking lot). Pizza was good. Room was okay and clean. Checked online - Kobarid is now "touristed" and didn't recognize the place. Sorry.