As long as people have been building boats and ships they have been sinking. And as long as people have been able to dive under the water they have been going down to look at these sunken ships. There is a magical and mysterious lure to that part of our history resting undiscovered on the bottom of the ocean. Scuba divers dive on wrecks for several reasons. Some seek treasure and profit. Some are professional or hobby archaeologists and are interested in historical information. And other divers just enjoy the excitement and adventure of visiting a ship wreck.

Safety is the biggest concern for all scuba divers but even more so for wreck divers. There is a risk of becoming trapped or lost in a wreck. Special training is available to scuba divers where they learn how to use special equipment. Reels of line are used to lay down a safe path through the maze of a ship wreck. Extra tanks of air are slung from the diver. Powerful underwater lights are required to light up the darkness. Wreck divers learn how to plan their dives so that they use one third of their air to reach the wreck, one third of their air to enjoy the wreck and return to the surface and hold the last third in reserve in case of emergency. Wreck divers have to especially cautious of hazards such as sharp and jagged metal.

Many recreational divers enjoy diving on artificial reefs. These are ships that have prepared and sunk on purpose in especially designated spots. Divers can practise their skills in the relative safety of a ship wreck that is well-mapped and sitting a safe depth. These ship wrecks are called artificial reefs because they soon become the habitat for corals, anemones and creatures of all kinds. Some artificial reefs will host up to four times their own mass in living creatures.

Most divers adhere to a policy of "non-disturbance" This means they do not interfere with the wreck or carry anything away. It is only fair to leave the ship wreck untouched so that other divers can enjoy it. But the environment soon starts to change the wreck. Breakers pound the metal or bust up the wood. Down deeper, currents carry away loose pieces and scatter them across the ocean floor. Even the creatures that make the wreck their home slowly start to break it down.

There is a compelling beauty to a sunken ship and great sense of adventure and challenge to learn the skills and become a wreck diver.