Narva, Estonia

Narva is Estonia's third-largest city, with roughly 57,000 residents sitting along the Narva River directly opposite the Russian city of Ivangorod. Only about 200 meters of water separate the two, marking the European Union's eastern border. Hermann Castle, founded by the Danes in the 13th century, faces the Ivangorod Fortress, which was built in 1492 on the opposing bank. The Alexander Cathedral, consecrated in 1684, ranks among the oldest surviving structures after World War II destroyed roughly 90 percent of the city. Around 84 percent of residents speak Russian, and the story behind that balance runs deep.