Must be roads you've experienced first-hand, not heard are good on some forum full of biking has-beens.
For me it was the road from Passignano sul Trasimeno to Citta di Castello in Umbria. Went to Lago Trasimeno, just because it's a lake and probably worthy of a look, had a nice cup of coffee and set off having punched a random destination in Maps that was on the way to Arezzo, just because it sounded good. The road set off from the lake, climbing in ever tighter hairpins, with views over the lake and beyond to the right, the autumn sun reflecting off the water. Topped the hill and then more of the same hairpins down to the farmlands below, just occasional hilltop towns with centuries-old church towers sticking out.
Citta di Castello was a bloody great disappointment when i got there. Not a castle in sight.
I can honestly say it was my best day's riding ever. The road was challenging, but exhilarating and the views stunning. I was tempted to stop and take pictures, but then thought, 'Bollocks, just enjoy the ride'. The only downside was there was nobody to share the experience with as I was Billy NO-Mates on that trip.
