Baltic Sea Cruise

Thanks guys so much for all your suggestions about tours. We have already
booked one with the cruise line but thanks to your suggestions, we will use
one of those suggested for the other two days.

Now another thing, in reading the information about the ports we will be
visiting, only one accepts dollars That being St. Petersburg. the others
either use Euros or local currency.
My question is where would be the best place to exchange dollars for either
Euros or local currency. I have been told that the ships do not give you a
good rate of exchange. I wonder should we do it at the airport where we
first. start the cruise? Would they have the other kinds of currency for
the other countries? Should we try to buy the Euros at a local bank over
here before we leave?
Thanks again for all your help.
Sandy