The world got you down? Wish you could escape to somewhere calm, beautiful and quiet? No problem! Just hop into one of these amazing one-man submersibles, take a deep breath and propel yourself down into the deep blue sea. Serenity awaits.
This is the Nordenfelt I, 1884 brainchild of Swedish inventor and industrialist Thorsten Nordenfelt 1884
Picture: Wikimedia Commons
One of the two Resurgam, an early Victorian submarine designed and built in Britain by Reverend George Garrett in 1878-79. The Resurgam I was a hand-powered, one-man submersible; the Resurgam II had a three-man crew and was steam-powered.
Picture: Garrett/Henry Guttmann/Getty Images
A submarine motor car, invented by Michel Andre in 1937.
Picture: Horace Abrahams/Fox Photos/Getty Images
The Motorised Submersible Canoe (MSC) -- nicknamed 'Sleeping Beauty' -- was a British underwater reconnaissance or attack vehicle for a single frogman during World War II.
Picture: National Archives of England, Wales and the UK Government
The Biber, a German midget submarine of the German Navy during World War II, came armed with two externally mounted torpedoes.
Picture: geni/Wikimedia Commons
The Welman submarine was a WWII one-man British midget submarine developed by the Special Operations Executive, but it was not very successful.
This K-250 one-person submersible was designed by retired US Navy WWII submarine captain George Kittredge in the 1960s.
Mikhail Puchkov's homemade personal submarine made a splash in the 1980s.
Picture: Mikhail Puchkov
This is the one-man microsubmersible Mantis, designed by Graham Hawkes, British marine engineer and submarine designer. You might remember it from For Your Eyes Only.
Picture: Osel979/Wikimedia Commons
C-Quester was one of the first mass-produced personal submersibles by the Dutch U-Boat Workx. Production was discontinued in favour of multi-passengers subs.
Picture: U-Boat Workx
Newtsub Deepworker 2000, a single-person submersible by Nuytco Research.
Picture: NASA Analog/Flickr
Deep Rover, another single-person submersible by Nuytco Research.
The Innespace Dolphin prototype personal watercraft, which can ride on top of, leap out of, or dive under the water's surface.
Picture: Scott Olson/Getty Images
AquaVenture WaterCrafts prototype sub, 2010.
Virgin Oceanic Expeditions' deep sea submarine, seen here in 2011, is currently still undergoing testing.
Photo: Reed Saxon/AP
James Cameron's Deepsea Challenger made it about as far underwater as you can go.
Omer 8, a human-powered submarine recently built by students of the École de technologie supérieure (School of Higher Technology) in Montreal, Quebec.
Top picture: Mikhail Puchkov