My friend and I are going to Germany in October we have a total of 14 days. We would like to make it over to St. Petersburg and back while stopping in other countries in between. Any suggestion on what countries are a must? Should we rent a car or travel by train? Is 14 day enough ( not that any amount of time is enough:) We enjoy all most all things from beaches to hikes to museum and history. This will be our first time in Northern Europe and would like to make the most of the 14 days. Any suggestion would be helpful. Thanks in advance for taking the time!