My family will be visiting Slovenia this year over Easter and staying in Ljubljana. We have one day to drive over to the coast (we'll have a car) and are debating Piran, which is closer, vs. a little longer drive down to Rovinj. If you had to choose one over the other, what would it be? If we went to Rovinj, I'd be tempted to drive back to Ljubljana thru Rijeka, across the Istrian Peninsula, but that might be too much driving in one day. Has anyone done this?
I'd pick Rovinj - but with a side trip (within your side-trip) to Pula. Rovinj is delightful, feels a bit like Venice turned inside out with a hilltown stuck inside. Pula is worth a couple hours, too - the amphitheater is awesome - it feels almost as big as the one in Rome but without the crowds. We drove past Rejika on the way from Istria to Plitvice, and it didn't look all that appealing (it actually looked kind of industrial). The area it's located in looked like it was worth exploring, but I'm not sure the city itself has that much appeal. It's going to be a bit of driving in one day but I think is doable.