In a low chamber inside, pigs amble across the ceiling. Two appear to be mating—unique for cave art, Ramli points out. Another, with a swollen belly, might be pregnant. He speculates that this ...

A mapping expedition in the Tlayócoc cave in Mexico led a professional cave explorer to a hidden chamber containing shocking ...

The Cussac cave is accessed by a narrow passage through boulders that have closed off its inner chambers for thousands of years. Lighting the way with headlamps, visitors cross vast chambers of ...

The Cussac cave is accessed by a narrow passage through boulders that have closed off its inner chambers for thousands of years. Lighting the way with headlamps, visitors cross vast chambers of ...

The Cussac cave is accessed by a narrow passage through boulders that have closed off its inner chambers for thousands of years. Lighting the way with headlamps, visitors cross vast chambers of ...

The Cussac cave is accessed by a narrow passage through boulders that have closed off its inner chambers for thousands of years. Lighting the way with headlamps, visitors cross vast chambers of ...