Plovdiv, one of the oldest continuously inhabited cities in Europe, carries over 8,000 years of history layered into its streets. The Roman Theater, still in use today, was discovered by accident in the 1970s and now hosts operas and concerts overlooking the Rhodope Mountains. Nearby, visitors can walk the remains of a Roman stadium buried beneath the main pedestrian street, where modern shops and cafés stand above ancient foundations.

Potosí rises on the Altiplano of southern Bolivia and for centuries it was one of the richest cities in the world because of what lies just beyond its streets. At the foot of Cerro Rico (“Rich Mountain”), silver was discovered in the mid-1500s, and within a few decades the city became a center of mining and wealth that shaped global trade and economies.

On Cook Strait sits Wellington, New Zealand's charming windy city. Must-sees here include the waterfront, the lovely beaches, and the Wellington Cable Car that takes riders to botanical gardens. For cultural exposure, visit The Museum of New Zealand Te Papa Tongarewa, with its Maori national treasures and art gallery. Wellington Zoo is another key attraction, and features Tahi, a one-legged kiwi, as its mascot.

Set in a wide alpine valley beneath the north face of the Eiger, Grindelwald has long been a place where mountain life and mountaineering history intersect. The village grew from a farming settlement into one of Switzerland’s earliest alpine tourism hubs in the 19th century, when climbers, writers, and scientists arrived to study—and attempt—the surrounding peaks.

The River Nile, most often associated with Egypt and its ancient civilizations, actually flows through eight other countries including Uganda, Ethiopia, Sudan, and Kenya. It is formed by two major tributaries, the White Nile and Blue Nile, and is considered by many to be the longest river in the world when measured from its source waters in Rwanda and Burundi.