Sopot, Poland

Sopot is a Polish resort town of roughly 35,000 residents on the Baltic coast, wedged between Gdańsk and Gdynia, with a population that multiplies several times over each summer. Its wooden pier, opened in 1827 and extended to 511 meters, ranks as the longest such structure in Europe. The Forest Opera, an open-air stage with a retractable roof built in 1909, hosted the Sopot International Song Festival launched in 1957 for decades. Nearby, the 1909 Grand Hotel accommodated guests including Marlene Dietrich, Charles de Gaulle, and Adolf Hitler during the interwar years.