This story appears in the June 2019 issue of National Geographic magazine ... two of the top three largest known caves in the world. To get there, a punishing path and 90 percent humidity test ...

Set between dramatic mountains and miles of coastline, this lesser-known region offers stunning scenery, outdoor adventure, ...

When hundreds of eerily perfect circles were discovered on the bottom of the Mediterranean Sea, theories abounded about what they could mean. Four years of underwater research revealed a lost world.

Trek through alpine peaks, underground caves, and historic battlefields in this under-the-radar adventure hot spot.

A photograph of a vertical pit entrance to the cave, called Crookshank Hole, appears in the June 1964 issue of National Geographic, and in 1976, it was discovered that the cave connected to the ...