While all that is very cool, there’s one downside to riding in a deep sea submarine: you might end up sounding pretty silly. Submarines are pretty cool bits of kit.

Is the Atlantis Submarine Cozumel Tour worth it? Absolutely! Here's everything you need to know, including the downsides, from someone who's done it.

High-definition pictures of a World War I-era U.S. Navy submarine that sank to the bottom of the ocean near San Diego were just released, over a century after it was lost at sea.

Chinese deep-sea science and engineering research vessel Tan Suo Yi Hao returning to port after completing deep-sea testing on October 3, 2017, in Sanya, Hainan province, China.

Submarines have captivated imaginations and dominated nightmares for much of the 20th century, but undersea vessels have a much longer history than that.

A deep-sea training and engineering dive off the coast of San Diego provided an opportunity for never-before-seen imagery of the U.S. Navy submarine USS F-1, lost at sea in an accident on December ...

Virgin Group founder Richard Branson, known for such exploits as trying to balloon around the world, said on Tuesday he planned to explore the deepest parts of the world's oceans with a jet-like ...