Submarines are a tremendous strategic and tactical advantage to countries that have them.
They range from small attack submarines used for naval and anti-submarine warfare to large ballistic-style submarines armed with nuclear weapons that could wipe out entire nations.
Launched in 1988, the Ohio-class USS Pennsylvania (SSBN-735) is currently the largest vessel in the U.S. Navy’s arsenal. It is 560-feet long and berths 165 sailors, according to the National Geographic video below.
Also see: 27 incredible photos of life on a US Navy Submarine
This video shows the ship’s incredible fire power, tactics and what life is like for the crew that man it.
Watch: