I ride it opposite way and first I thought it is 3 star or 4 star road, but closer I get to Vienna the better corners were
stegoa 350km pure pleasure ride in an absolutely stunning countryside with all sorts of challenges for mature and experienced riders. allow yourself quite a few brakes, first because the landscape wants you to and second your concentration level and body fitness wants you to. i have been riding bikes for 22 years and this trip is on the top of my list. unforgettable indeed.
ride safe and enjoy...