South Tyrol (German: Südtirol) is the Province of Bolzano-Bozen (Italian: Provincia autonoma di Bolzano; German: Autonome Provinz Bozen; Ladin: Provinzia autonoma de Bulsan), also referred to in English as Alto Adige (from the Italian name) or South Tyrol (from the German name Südtirol) is an autonomous province of Italy.
Bolzano towards Innsbruck, This might be tricky. There is a roundabout, but not too much space for cars to stop. It might be better to find a spot closer to the city centre. If you're into that sorta thing, for 15 euros you can take a train all the way to Kufstein, which is very close to the German border.
You can also try the "statale" going North, which is Via Brennero.
15.07.2020 We (guy and girl) hitchhiked this route, we started on the bridge next to the highway, it is not the best spot but there is room for cars to stop on the island. Most of the traffic was going to trento but we got a lift after 15 mins to the toll which is a better spot and from there a lift all the way to Rosenheim within 5 minutes