It is VERY expensive to anchor or dock your boat within the Brijuni National Park. Acording to the park website berthing prices in July and August range from €170/night for less than 15 m to €780 for more than 40m. I think there is also a per person charge.
It was recommended to me to go to the marina in Fazana and catch the ferryboat to the Brijuni Islands that are meant to be fascinating.
The cost of the ferry includes the park entrance, I believe.
Marshal Tito had his summer residence there and collected many exotic animals.
www.brijuni.hr/Howard [ Just Imagine ] 12-Jul-2007