Originally Posted by Pecha72
Yes, Helsinki is in Scandinavia.
It is in the Baltic Region, just not in the Baltics (which refers to the 3 Baltic States).
I'm curious why the OP posted Helsinki/Tallinn as a destination and along what route he wants to return to Germany by bike.
When I was in Finland I met a German couple who did what the OP wants to do: they took the ferry from Travemunde to Helsinki and drove back to Germany, first going up through Finland, to the Northcape and then back through Norway.
People I know that went to Tallinn by ferry all rode back through the Baltic States and Poland.