Excellent ride through a mountainous national park in Montenegro (Crna Gora). The route I took was through Durmitor, Montenegro's premier national park (a great ski destination in winter), on a narrow road 1.5 lane road in late May, 2018.
There was some snow remaining on the side of the road in parts, but any moisture on the road was snow melt (water) and not icy. But, the elevation is such that there could be issues with snow and ice on the road in anything but high summer.
I have some pics, but for the best idea of what this road is like, please watch the 7-minute YouTube video I will upload.