<map lat='54.42372401996794' lng='18.5394287109375' zoom='9' view='0' float='right' height='350' /> Sopot is a seaside town in Nothern Poland, it has the longest wooden pier in Europe but sadly there is nothing to hitchhike on it. Sopot is also the smallest of the Tri-City with Gdańsk (to the south-east) and Gdynia (to the north) Your best bet would be to start in one of those city.
If you're not feeling like taking the train to Gdańsk or Gdynia, the best place to start would probably be on the main road going trough the city just behind the Train station.