That used to be the road connection from Ponte Arche to Sarche. Hard to believe! Was totally decayed and overgrown in some places, before they decided to build a bike path out of it. For racing, trekking and mountain bikes equally suitable (very good surface). The serpentine rise from Sarche until the beginning of the way is busy, but not steep.
The ascent from Sarche is worthwhile, but he is (as already described) not very pleasant, because there is no bike path. The bike path in the gorge is then again …