For centuries, man has found countless ways to send ships to the bottom of the sea. Since the advent of scuba technology, we’ve found ways to explore them. Whether it’s to search for booty, take eerie photos, or just to pay respects, wreck diving is a not a sport for the timid. Often found in deep, cold water with strong currents and dangerous reefs, wrecks demand expertise, experience, humility and marine-grade bronze balls — not to mention a lot of specialized gear. This isn’t tropical holiday diving, so be prepared to shell out for equipment that can stand up to the conditions the Gunilda, the Thistlegorm or the Doria present.