Leave London at 1602 to arrive in Paris at 1917. Catch the 2020 from Gare de l'Est and arrive in Berlin at 0859 next day.
See Anna Shepard's article on whether Hamburg lives up to its reputation as Germany's greenest city and how it compares to Berlin: Hamburg: Germany's greenest city?
Read Sally Broom's featured article on Travelling by train from London to Nuremberg.