In the southern deserts of Peru, Nazca invites visitors to look beyond the horizon. This small city is world-famous for the mysterious Nazca Lines, enormous geoglyphs etched into the desert floor more than 1,500 years ago. From the air, shapes like hummingbirds, monkeys, and even a stylized astronaut come into view, some stretching over 300 meters. Their exact purpose remains a mystery, fueling decades of theories.

One of the major rivers of the Iberian Peninsula, the Douro in north-central Spain and Portugal just might be the world's most beautiful wine region. Most of the river on the Spanish side isn't navigable, so river cruises generally travel roundtrip from Porto, on the coast of the Atlantic.

Berat, set along the Osum River in central Albania, is a city shaped by centuries of continuity and coexistence. Known as the City of a Thousand Windows, its white Ottoman-era houses climb the hillside toward a hilltop fortress, creating a striking and harmonious skyline.

A relatively recent addition to Costa Rica's list of national parks is Tenorio Volcano National Park, home to its namesake Tenorio Volcano as well as its taller sister, Miravalles Volcano, also the highest mountain in the Guanacaste Mountains.

Cambridge, Massachusetts, sits across the Charles River from Boston and is known for its universities, historic neighborhoods, research institutions, and distinctive network of public squares. Harvard University and the Massachusetts Institute of Technology give the city an international academic profile, while areas such as Harvard Square, Central Square, Kendall Square, and Inman Square each have their own mix of shops, restaurants, cultural venues, and businesses.