I'm planning a trip to Croatia in May 2012, and am trying to get a reasonable estimate for driving times. We will have a rental car.
We're planning to spend two days driving around Istria (after a day in Rovinj). The first day, we will drive from Rovinj to Pula, spend a few hours in the morning visiting the amphitheater and other Roman ruins, then I plan to head north into the hill towns for the afternoon - maybe Buje and/or Groznjan, then spending the night, probably in either Groznjan or Motovun. The next day, we would continue to explore a couple other small Istrian hill towns (maybe Zavrsje?) in the early part of the day, then after lunch continuing on east to Opatija for a short stop (maybe just hanging out for an hour or two before an early dinner), then driving to Plitvice. We plan to spend the night at Plitvice.
My question is: how much time should we allow for the drive from Opatija to Plitvice? And what is the best, most logical (shortest) route when driving this route?