Caves

Each of the boys was sedated with ketamine and their hands were tied during the rescue extraction mission.

Dr. Pak Loharnshoon of the Royal Thai Army visited the group on Monday while they recovered at a hospital in Thailand.

All 12 boys of the Wild Boars soccer team and their coach have been evacuated to safety.

Petty Officer Saman Kunan ran out of oxygen while negotiating the cave's narrow tunnels.

The team will either have to learn to dive in treacherous conditions or wait four months for the waters to recede.

The treasures are at risk of ruin, the researchers warn.

When the crocs reach their full size, they become trapped inside the caves for the rest of their lives.

The cave stretches more than 200 miles.

There's no other way to access these unexplored areas than to strap on your scuba tanks and jump in.

Among the thousands of artifacts were fossilized skeletons of rabbits, sheep, donkeys, rhinos, bears and birds.

The first two modern human cultures coexisted for many years, but until now it's been unclear if one was borne from the other.

For as much as it might reveal about ancient island cultures, the art itself is incredibly tiny.

The caves have eerily straight walls and ceilings, and sections are full of water.

The humpback golden line barbel also has a mysterious little horn.

Subterranean spiders serve as harbingers of environmental dangers to come.

A newly discovered inch-long millipede has more legs than the chorus line at Radio City Music Hall.