missing submarines

Australia's first submarine was found after more than 100 years of disappearance
According to Phys, the AE1 ship disappeared on New Guinean Island in New Britain on September 14, 1914 with a fleet of 35 people from Australia, England and New Zealand.
The most mysterious mystery submarine cases in the world
Submarine is a very unique underwater war machine. It was designed to operate secretly underwater to carry out reconnaissance, reconnaissance missions, deploy commandos and fight.