The road starts in Starigrad Paklenica, and from there ascends uphill almost all the time. Right from the start, there are two great view spots. You can get there with any kind of bike, the road is paved to this point. If you continue further, after 5-7km, the paved road stops and the gravel road starts. I went with a naked bike, and everything was fine, but as you climb more, the rocks on the road start to get bigger and sharper, so I was afraid that I don't puncture the tires. Great road if you want to explore Velebit.