Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.

Single runway interrupted by a busy road that cuts across its middle.

A set of ancient drawings in the desert of Peru that are so massive, many of them can only be fully seen from the sky.

An unexpected desert oasis in South America.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

Catacombs turned marketplace.