In reply to Liamhutch89:
I can't answer I'm afraid but I thought I might indulge readers in a very unsophisticated little rhyme I penned about 25 years ago. My wife and I spent a week in Istria (definitely her choice) followed by a week in the Julian Alps (definitely my choice). So:
"I wish it were cooler in Pula,
"I don't want to singe in Rovinj,
"So take me instead to the lake they call Bled,
"And there let me have my revenge."
By the way, if you're heading that way the show caves at Postojna are very special - for the whole family I would suggest. Quite the most spectacular I've ever seen.
Martin