You may have heard of a sinkhole on a piece of land, but what about one in the middle of the sea? Here's a landmark that recreational divers have visited since the 1970s. The Great Blue Hole is a giant sinkhole located off the coast of Belize. It's part of a barrier reef known as the Lighthouse Reef Atoll in the Caribbean Sea. Looking down at the Great Blue Hole from an airplane, you'll see a dark blue circle measuring 1,000 feet (300 meters) wide surrounded by light blue, more shallow water and a reef.
A boat will take you to this sought-after dive site. Since the Hole is 400 feet (125 meters) deep, you'll need to prepare well in advance and get your scuba diving certification before exploring the caves and stalactite formations at the bottom. It's a heart-pumping and exhilarating experience that's not for the faint of heart, but its beauty is worth the effort.
As you can see, a fit body is about more than looking good and increasing your longevity -- it's about having the ability to visit some of the most amazing places on the Earth. For lots more information about fitness and famous landmarks, turn to the next page.