Want to get an up-close look at what goes on under the water? Your best bet is scuba diving.  Strap on a tank of air, pull on a mask and a pair of fins, and you can explore the 70 percent of the globe that lies underwater.

You don't need to be a Navy Seal or Jacques Cousteau to go scuba diving these days, but the sport does still have its dangers. You will need to take a certification course before you adventure underwater. These courses, ranging from a few days to months, explain how to use the equipment and stay safe.

Once you've learned the ropes, where do you go? Though there are a hardy few who go in for ice, cave or night diving, most recreational divers prefer warm, clear water with lots of marine life. It is also possible to dive shipwrecks.  Some of the world's best diving can be found in Cozumel Mexico, many islands in the Caribbean, Belize, and the Florida Keys. For those looking to travel further abroad, Palau, Bali, the Philippines, the Red Sea, and the Great Barrier Reef all offer amazing underwater sites swarming with sea life.