From grand castles to resplendent cathedrals, Tallinn’s Old Town neighborhood, a UNESCO World Heritage Site, is the perfect place to begin exploring. Enter through Viru Väravad, or Viru Gate, the former fortress whose remaining two towers beckon you into the heart of the city.

Osijek, located in the eastern part of Croatia, is a city that blends rich history, vibrant culture, and a lively atmosphere. Situated along the banks of the Drava River, Osijek is the fourth-largest city in the country and the cultural and economic center of the Slavonia region.

Guadeloupe's major center is Pointe-à-Pitre, a conglomeration of old and new buildings clustered around the bustling harborside market. Pointe-a-Pitre is Gudeloupe's most popular city--explore the beaches of Grand-Terre and the French fort ruins and volcanic mountaintop of Basse-Terre.

Originating as a tiny fishing village in 1038, modern Kehl has become an important link between Germany and France. Rhine River cruises most often use Kehl as their gateway to the much larger and better-known Strasbourg. The savvy traveler, though, might choose to skip the jaunt across the river and enjoy many similar sights, shopping and cuisine as those offered in the teeming French city.

Tromsø, a gem nestled in the Arctic Circle, offers an unparalleled blend of natural wonders and cultural richness. Known as the "Gateway to the Arctic," this Norwegian city is famed for its spectacular Northern Lights. Between September and April, Tromsø becomes a prime location for witnessing the aurora borealis, a mesmerizing display of green, purple, and pink lights dancing across the polar sky.