Long before humans began transforming the landscape in Portugal, nature had already fashioned some incredible sights ...

Carved into granite with mirror-smooth walls and perfect lines, the Barabar Caves show a level of skill far beyond their time. Their construction remains a mystery in ancient engineering.

Roughly 4.5 billion years ago, the young solar system was a swirling cloud of gas and dust that formed the first asteroids ...

Stretching like a colossal spine along western South America, the Andes stand as the world's longest mountain range. It spans ...