Visit the windmills of Kinderdijk

Storybook fortress on a rock island ringed by a river canyon.

The 50,000-seat amphitheatre where Rome staged its bloodiest spectacles for 2,000 years

Walk along the Great Wall of China, a UNESCO World Heritage site

Stand among the cloud-wrapped ruins of Machu Picchu, the 15th-century Inca citadel perched high above Peru's Sacred Valley

The torch-bearing symbol of New York.

Boulder-strewn ruins of the Vijayanagara empire along the Tungabhadra river.

Sanctuary of Apollo on the slopes of Mount Parnassus — home of the ancient oracle.

Rift-valley site of the world’s oldest parliament, where the tectonic plates pull apart.