The S-1 Blast Shelter is an underground complex beneath Szczecin's main railway station, built and adapted through the Second World War and Cold War. The tunnels make the city's twentieth-century fears physical: air raids, civil defence, secrecy, and the strange normality of preparing for catastrophe.
It is one of Szczecin's more distinctive visits because it sits below ordinary transport infrastructure rather than in a purpose-built museum district. Tours and opening times matter, so check ahead; the experience depends on guided access and the atmosphere of being underground.