Bolzano - Prazollsteig
Very nice tour that from Bolzano leads, with some nice strenuous ramps, to Matschatsch, from there continue on the state highway towards Mendola pass. Once at the pass continue in the direction of Monte Roen, past the Mezzavia hut you arrive at the start of the descent. Be careful, the first part of the descent is very exposed on a narrow path, it is not very difficult except for a few passages, but the exposure is quite a lot, so I strongly recommend to be very careful. As you go down the trail becomes less and less exposed, but not less technical, in fact it has some very tough switchbacks, in general the trail is very challenging. The second part of the descent, on the other hand, is much easier and smoother.
PS: on the downhill trail there would theoretically be a ban on bikes (it remains a very infrequently used trail anyway, so I find the ban absurd), so always give priority to pedestrians.