Grudziadz, Poland

This former Prussian city on the Vistula River has a population of around 90,900, but don't expect a warm welcome. Grudziadz has a long history of ethnic tensions and heavy-handed bureaucracy that make it a tough place for outsiders. The Nazis brutalized the Polish population here during World War II, and even after Poland regained control, the authorities remained suspicious of minorities. Expect a persistent headache dealing with red tape and an unwelcoming atmosphere. Unless you're a Polish nationalist looking to immerse yourself in the country's tumultuous history, Grudziadz is best avoided.