The two-man Delta submarine prepares to be lowered into the Dead Sea.

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Personal Submarines

For years, subs were mainly used for military purposes. Later on, marine science got into the game, using subs for close up viewing of sea life and shipwrecks. But like many things that started out with military and scientific applications, people soon realized that they could also be used for recreation. Personal subs came along in the 1970s, thanks to a man named Graham Hawkes.

Hawkes was one of the early designers of the mini-sub, originally building them to allow marine researchers to get up close and personal with the ocean floor. Years later, the jet set crowd got wind of the personal submarine and decided that they made a pretty nice addition to their yachts. If a 250-foot (76.2-meter) yacht can have a helicopter, a speed boat and a couple of jet skis, why not a submarine? The personal submarine has become a status symbol for the ultra-rich, an expensive toy for people with expensive tastes.

Most personal subs are built to be launched from the rear of a yacht, though some are small enough to carry and launch from a boat trailer. No one knows for sure just how many of these submarines are out there, and since the Coast Guard considers them boats, there isn't a way to log an accurate count. Each type of mini-sub is different from the next. They range from the do-it-yourself kit subs for about $18,000 all the way to luxury subs that sleep up to 20 people and cost more than $80 million. The 5,300 square foot (500 square meters) Phoenix 1000 submarine actually has an option that includes an even smaller, sportier personal sub.

With the difference in price tags comes a wide range of functionality. Obviously, the most expensive subs are more high-tech, comfortable and have a much greater range. The less expensive models tend to stay within 25 feet (7.62 meters) of the surface, but if you want to pay for it, you can go as far as 3,000 feet (914 meters) down.