Świnoujście, a city on the Baltic Sea in Poland, is generally a safe place to stay, even at night. It's a tourist town and is well lit, with ample security. Nonetheless, as it's often the case, extra caution should be applied late at nights, especially in deserted and unfamiliar areas. However, overall, serious incidents are rather rare here and it's fine to walk alone at night provided that standard safety precautions are taken.