Watching a school of sharks coming at you from the depths of the sea has got to be an adrenaline-pumping hit. But that doesn't mean you're in danger. Not if you're in a shark cage with a crew that knows its stuff.

The cage, which floats on the surface of the water, is designed to keep sharks out, not capture them. You'll be in a cage with plexiglass windows, maybe nose to nose with a shark, but definitely out of harm's way. These multi-sensory creatures, which predate dinosaurs and have been around for at least 350 million years, are as fascinating as they are dangerous. To observe them without fear of attack is an awesome experience.

There are several companies on Oahu that are in the business of providing that experience. Tours depart daily from the Haleiwa Harbor on the island's North Shore. Floating on the ocean's surface, the shark cage provides visibility of approximately 200 feet making it possible to see sharks coming up—and at you—from the deep. You can expect to see sharks ranging from 5- to 15-feet just inches away from the cage.

With the exception of man, the shark is considered nature's most perfect predator. This is a creature that, as an adult, grows seven- to 12-sets of teeth a year, has no breakable bones and actually possess six highly developed senses.

On a shark tour, passengers can expect to see gray reef, Galapagos, sandbar and hammerhead sharks. The early Hawaiians worshiped shark gods. In Hawaii, each island had a different god. The king shark god of Oahu is Kamohoali'i, who is said to reside in an underwater cave near Pearl Harbor.