Colombo is the financial capital and by population, the biggest city in Sri Lanka. A major trading port as far back as 2,000 years ago, Colombo has an expansive harbor, making it a true commercial center of this island country.

Cuba is a multicultural nation and the largest island of the West Indies. Its waterfront capital is Havana, a musical, scenery-rich city that is the center of commerce and tourism. Walk the Malecon of Havana, marvel at the artworks in the Museo Nacional de Bellas Artes, and go for a refreshing swim on Cayo Coco in central Cuba.

Berlin has an undeniable history. The horrors of World War II, division, reunification, revolution all profoundly impacted the city in the 20th century. Today, visitors will find a sophisticated, high-energy city with endless cultural, architectural and gastronomic attractions.

Ancient history comes alive in Athens, the capital of Greece. Gaze in wonder at the Acropolis and its iconic crown, the Parthenon. Take a deeper dive into the past and visit both the Acropolis Museum and the National Archaeological Museum, which house fascinating artifacts from this ancient city.

Washington D.C. is the capital of the United States and home to some of the country's most iconic landmarks and monuments, including the White House, the Washington Monument, the Lincoln Memorial, the Smithsonian National Museum of Natural History, and the Capitol Building.