Have an 8 day cruise with Viking from Athens to Venice in October. Want to spend 7 nights in Rovinj as a home base to explore Istria. Will rent a car in Venice and drive with 7 days (that includes the ship departure day and the arrival in Rovinj day) or 6 nights on the road. I don't like spending less than 2 nights anywhere so we could have 2 or 3 places to explore before we settle in Rovinj. We'll return the rental car to Venice and spend one more night there before flying home. I have not included Plitvice as a daytrip from Rovinj because I think it's too much of a roundtrip drive for a daytrip.
We are seniors and like to have time to absorb the cultural atmosphere. We also don't like to put more than 5 hrs. of driving in any day. I think I'm scheduling about 3hrs and some less.

For the road trip section ahead of Rovinj should we spend 2 nights in Trieste, 3 nights in Ljubjana (one of those days a daytrip to Bled) and one night in Plitvice before arriving in Rovinj? I realize I'm breaking the 2 night rule here. So should we just forget Plitvice and spend the extra day in Ljubjana?

Or instead of Trieste should we consider going to Padua? We've never been there. We've seen Venice before, spent a full two weeks for Christmas in Rome, and have done Naples, Assisi, Milan, Pisa, and Florence well.

Just one more question. I think I should book rooms that are not in the old town of the road trip towns because of the ease of parking, unpacking and packing back up. It means we'll need bus transportation into the old town and other areas of interest but maneuvering a car and paying for parking in a garage seems more hassle than it's worth. However, I plan to stay in the old town in Rovinj and park the car in a free lot or apartment owner's provided spot that will probably not be all that convenient. I just think I need the old town ambiance there. Does this make sense?

I'd certainly go to Plitvice. It's amazing. So what if you break your one night rule once? For convenience, you might stay at one of the overpriced park hotels. You can walk right into the park from the hotel, and if you want to explore Plitvice over two days / one night, you can get your tickets stamped at the hotel front desk to enter a second day on the same ticket.

I would try to find lodgings in each place with good parking options but still not far outside the center. Ljubljana has huge pedestrian-only areas. But it's a small town, so you can park in various places right on the edge of the old town and still walk into the center easily. Most lodgings will indicate whether they offer parking or not - and if not, they should be able to tell you where you can park. I would not want to say outside of Ljubljana's lovely core.

You could consider using public transportation for part of your trip and rent the car only for say Croatia and/or Slovenia. You can take a train from Venice to Trieste and a bus from there to Ljubljana (if you fancy trains, there's a way to get to Ljubljana from near Trieste but it requires a bus or taxi transfer to Villa Opicina or Sežana. There are direct shuttle services between Venice and Ljubljana too. You wouldn't necessarily need a car in Ljubljana itself - easy to get to Lake Bled by bus or even train, but there are some pretty drives in and around Lake Bled, so having a car would let you do them.

I've been both both Padua and Trieste but years apart, so it's hard for me to compare them. I didn't fall in love with either one of them, honestly, but I don't think it's a mistake to visit either. Trieste may make more sense on this trip because it is kind of on the way, and perhaps on some future trip Padua will be on the way to somewhere else in Italy.

Given your preferences, I think your plan makes sense.

The Plitvice Lakes National Park is, IMO, the single most un-missable of Croatia's many splendors. Not only are the lakes connected by travertine waterfall formations, each lake has unique microbiota, and as a result, the lakes are different colors. The best way to see that is to make a single, long loop through the park -- something on the order of 6 hours or more (including time for the boat that connects the lower and upper lakes), and by all means, start at the lowest part of the park so you are facing the falls as you proceed. For many of us, that means one night in the area, but some people prefer the night before and the night after. Your call. Most of the guesthouses in the area are known for serving dinners with incredibly fresh fish.

If 3 nights in Ljubliana means 2 days – one for Ljubliana and one for Bled – you might want to add a night for Lake Bohinj and one or more of Slovenia’s magnificent caves (e.g., the Skocjan Caves). You can, I think, take a night from Rovinj for that.

I trust you have considered the drop-off fee for renting a car in Italy and returning in Croatia? You might want to give some though to Andrew’s suggestions for public transportation.

Staying in Rovinj’s Old Town makes a lot of sense. FWIW, I was very pleased with the Casa Garzotto.
http://www.casa-garzotto.com

Enjoy!

>>Or instead of Trieste should we consider going to Padua? <<

Trieste is a fascinating place if you are interested in the complex history of port cities and Italan history in general. It also happens to be a peculiarly dynamic, cosmopolitan Italian city, with a local culture more like Barcelona or some other international crossroads than your typical traditional Italian city. The food in Trieste is like no other in Italy, an astonishing mash-up of influences, from Austria to Napoli to the Balkans and Jewish cuisine and yet more, and it is fun that way. Far from being "There is no there there" (as was once famously said of Trieste), it's actually quite hard to keep track of how much is there, or ended up there -- it's simply a wonderful early example of the power of globalization, and it is still alive that way.

Padova has a great deal more of the things that people typically come to Italy to see and experience. It is rich in outstanding art, has a unique university history, plus beautiful, truly "Italian" piazze and one of the most beautiful food markets in all of Italy. If you can't get enough of the treasures and marvels of Italy, Padova is not going to disappoint you, and of course you can also easily take day trips by train to other fascinating towns with castles and exceptional art treasures nearby.

I give a great deal of deference to Andrew and kja who were very helpful for our trip. (See my Trip Report.) And while we enjoyed virtually every stay, I think that aside from the cafes along the harbor, the center of Rovinj was about the least interesting town. If we had it to do over, I'd stay in Porec as a base for Istria. But if you do want to stay in Rovinj, I'll put a plug in for Villa Dobrovac: minutes up the hill from the big parking lots just outside of centro and a very easy out for day trips.
As for Padova, we loved it especially the Scovengi Chapel. But we like to "keep our heads" in the one country we're visiting. (Although Ljubljana is in Slovenia, we found it geographically and conceptually closer to Croatia/Istria than Padova.) So, I'll second what I think is massimop's suggestion and take in unique Trieste instead of Padova.

@ PaoloCast2: thanks!

I really loved little Rovinj. I was there just before the season started in late April-early May, so there weren't that many tourists yet. I'll bet October would have a similar feel. I was there on May 1 - a holiday in Europe - and a local school band came out to play in the little town square (or what passes for one). All the parents were there watching them. I'd probably enjoy a visit in October - but not in the summer, most likely.

The twisty streets winding up to the top of the hill and the church had artsy tourist-oriented crafts for sale, but the general setting made it feel unique. I'm not sure I found the town interior itself (the shops and restaurants) that interesting. What I really loved was walking around in the morning, some of the local fishermen were getting their boats ready, when it was really peaceful and quiet. And I loved coming back to Rovinj at night - a lovely setting by the ocean in the moonlight. I see Rovinj more as a nice base to explore Istria than as a destination to visit in itself.

I enjoyed both Rovinj and Porec, which I found quite different from each other. I'm not sure I can describe the differences well, but FWIW:

I found Rovinj to be a tourist destination. Yes, people live there, but the main function of the Old Town -- the part tourists are most likely to see -- seemed to me to be to support tourism. It has some lovely nooks and crannies, some beautiful vistas, lots of cafes with opportunities to watch the water or the strolling passers-by, and lots (LOTS) of shops selling arts and crafts and souvenirs. Unlike Andrew, I did not find this street of arts/crafts stalls unique; I found it all-too-predictably like countless others I have seen. But at least the artisans weren't pushy, so I didn't find them off-putting.

Although the historic district of Porec is very small, it didn't feel to me as dominated by tourism; rather, it seemed to be a part of a vibrant local city. The Euphrasian Basilica is a gem, IMO, well worth seeing from any Istrian base. IIRC, unlike Rovinj, the Old Town of Porec doesn't have a hill or other elevated area that would afford the kinds of glimpses out to the water that Rovinj offers at just about every turn.

Personally, I enjoyed roaming around Porec more than roaming around Rovinj, but I spent only a few hours strolling around each. For a stay of multiple days, I can easily imagine preferring Rovinj for the variety of different views one can get over the sea when stopping for a meal or break.

Hope that helps!