For centuries, humans have lived underground. Today, that ancient practice is under dire threat—even as cave life makes more ...

There are some places in the world that are so unusual, so mystical, so strange, so stunning – that it is hard to believe that they belong on this planet at all. From peculiar geological wonders to ...

The Sahara wasn’t always a desert—14,000 years ago, it was alive with rivers, people, and wildlife. Now, new evidence is ...

As the growing tide of travelers strains housing, water and hot spots, protests and measures to lessen the effects of ...