Robert Ballard leads an expedition in California's Channel Islands to test new underwater research techniques.

What it's like to witness a giant manta while hanging in the open ocean for decompression obligations.

Photojournalist Jill Heinerth surveys the fragile marine habitat in the Arctic, where melting sea ice has an ecosystem hanging in the balance.

Bell Island Mine is an underwater time capsule of a Canadian isle's heroic struggle to support a war effort while protecting a now-lost culture and way of life.

Cave photos can be absolutely stunning, but getting a perfect picture can be a challenge. Here's our tutorial on improving your skills!

Scientific divers deploy a technological arsenal to explore a twilight zone of Ice Age reefs in Bermuda.

Thinking about getting certified to scuba dive in caves? Caver Jill Heinerth tells us why she loves cave diving, and what the experience is like.

Alexander the Great thought that Egyptian Desert Springs were connected underground, and this team of tec divers brave the Arab Spring to trace his footsteps.

Jill Heinerth recounts what it's like to get bent or suffer from decompression sickness, or DCS, after advanced scuba diving.