Julie Cesar gave it name Una, #1 river in Roman imperia.
So you will have fun paddling class 3-4 rapids also some serious falls, water is still green.
It is save now, friendly people, like strangers, the best time is from April to July when water get too low, and again from the middle of August is still good. Winter time or early spring no people on river.
Enjoy.
Link:
http://www.travel.maestral.hr/bih/unarafting.htm
