The HMS M1 was constructed during WW1 but was never used in combat due to fears the Germans would copy its revolutionary design.

A group of divers have explored the wreckage of a WW1-era Royal Navy submarine 100 years after it sank. Dominic Robinson, 54, ...

As World War I came to an end, Germany was forced to surrender its fleet to the Allies, including the massive U-118 submarine. The French took possession of the vessel and set sail for her new home, ...

The navy's few primitive ocean-going submarines and an entirely new type of small warship, aptly named the subchaser, helped secure an eventual victory over the U-boat.