The 408 is a gravel road (for the most part), that runs from Drvar in the north, and south east towards Glamoc, where it meets the M15.
It is a smooth, flat road in the wide valley, and carves its way for 48 kilometers. If this won’t give you the feeling of freedom, I don’t know what will.
On the way, at a village called Rore, there’s a couple of ruins of old houses, that is worth a stop. There are no shops, it’s in the middle of almost nowhere.