The length was only about 130 km, with two passes at 2056 and 2239 meters, respectively. We used Mountainbikes, but the same tour can easily be ridden with road bikes. Many interesting others in the same area require mountainbikes, though. Mt. Marmolada is in the central Alps. I had this mental image of snow-capped peaks and vertical cliffs that could not possibly allow any reasonable bicycle riding.
Roads usually wind their way up or down in serpentines.
I live in Berlin, which has only very minor hills, and I am a poor climber, but I found that I can manage a pass or two a day in the Alps without too many problems. The reward of the trouble is awesome scenery. The left picture shows the dam that closes off Lago di Fedaia at its western end. There is a two-lane road on top, the tiny dots in the picture are cars. We crossed the dam attempting to find a trail to cross over the mountains towards Passo Pordoi, to avoid having to ride on roads.