The Challenges of Geography

I am planning (hoping?) to take my father to Berlin this summer.

This seemed straightforward enough at the beginning, but pretty soon it started to get more complicated:
  • We start with the week in Berlin (a city where I have a good friend) for his reunion.
  • He wonders if we can go down to Berchtesgaden and that is pretty straightforward too - especially if we begin or end our trip at the Munich airport.
  • We both agree that while we are so close, we should run up and visit the cousins (his father's family) in southwestern Sweden.
  • He wonders if, while we are so close, we could make a quick side trip in Norway so he can say he has been there and I recall Oslo (not so far from our cousins and right on the main rail line) as a lovely, easy to navigate town and decide we will spend a day or two there.
  • My brother wonders if he might be in Finland about the same time we are wandering around Germany and Sweden, which makes me realize my father has never met his mother's relatives who I THINK live somewhere in the Swedish-speaking area along Finland's southwestern coast, so I add them to the list.
While a bit of a complicated itinerary (it doesn't make an easy loop because you either need to go up to Tallinn and cross over to Finland, take a very long ferry/cruise ship trip from Germany, or back-track through southern Sweden), it still seems doable if we have three weeks rather than two. . . until I realize that the cousins in Finland are way, way up the coast (below the Arctic circle, but not by much). How do I make THAT work? But how can I not take advantage of an opportunity for my dad to see where his mother grew up and meet his cousins there?

It leaves me with the need to connect the following dots in some rational way:

View Baltic Summer 2010 in a larger map

All suggestions welcome.