Four days out, from the passes to the cities
You pick a valley and stay there: everything else is a day trip.
The region is not comfortable to cross: the valleys run parallel and to move from one to the next you have to go over a pass. So it makes sense to think in terms of days that start at the campsite and end there, rather than long routes. These four can all be done in a day, three by car and one on foot.
The four passes loop
It is the Sellaronda: Pordoi, Sella, Gardena and Campolongo, a ring of about fifty kilometres around the Sella group taking in Val di Fassa, Val Gardena, Val Badia and Arabba. It takes half a day without stopping and a whole day if you stop, which is the point. In summer it is crowded with motorbikes; some passes have car free days, and those are the best ones for a bicycle.

Bolzano and Otzi
Bolzano can be walked in half a day: the arcades, Piazza Walther, the cathedral with its patterned roof, the fruit market that is there every day except Sunday. The reason to stay longer is the South Tyrol Museum of Archaeology, home of Otzi, the man found in 1991 at 3,210 metres on the border, dead for fifty three centuries, with his shoes, his bow and an arrowhead in his shoulder.
Trento and the Buonconsiglio
Trento is a city of a hundred and twenty thousand people with a compact, frescoed centre. The Buonconsiglio castle, once the residence of the prince bishops, holds in its Torre Aquila the Cycle of the Months, a fourteenth century fresco that tells the farming year month by month. The city also has Renzo Piano's MUSE, opened in 2013, which is where you go if it rains.
A day on foot
The Alpe di Siusi is reached by cable car from Siusi, and from there you walk on the level for hours across a plateau of fifty six square kilometres with the Sassolungo in front of you. Anyone who prefers water has the lake of Braies, where the full circuit is three and a half kilometres and anyone can do it; in high season the road is closed to cars from half past nine until four, and you go up by bus.