The most obvious day trip from Sopot is Gdańsk — 20 minutes by SKM train, and one of the most historically rich cities in Poland, with the rebuilt Old Town, the medieval Crane on the Motława River, and the entire arc of history from Hanseatic merchant city to Solidarity movement. Sopot makes a quieter base than Gdańsk in summer, with easy rail access in both directions.
Gdynia to the north is worth an afternoon: a modernist interwar city with a fine collection of Art Deco and Functionalist architecture, a naval museum, and a more local atmosphere than Sopot's resort bustle. Hel Peninsula — a narrow spit of land extending 35 km into the Gulf of Gdańsk — is reachable by boat from the Sopot Pier in summer, with good beaches and a seal rescue centre at the tip.
