Since the beginning of time, men have gone into the water—some to collect food—some to see what lies beneath the waves. It’s hard to actually tell the exact date of the first dive, but we do know from recovered artifacts that the people of Mesopotamia dived to collect pearl oysters—and that early diving took place around 4,500 years ago. Later the Greeks of Thebes would dive for pearls and the Chinese were not far behind.

Sponge fishermen are mentioned by Homer even as far back as 1000 B.C. Those sponge fishermen had a technique that involved plummeting to extremely deep depths by holding a rock. They would try to work around the pressure on their ears by pouring oil into their ear canals and mouths. Once at the bottom of the ocean, they would spit out the oil, cut as many sponges free from the bottom of the ocean as they could, and then the divers were hauled back to the surface by a line.

Divers had also been used by the military long before the birth of Christ. The Athenians and Spartans were the first known military nation to use divers, and Alexander the Great is well known for using “demolition divers” to clear obstacles from harbors.

Of course, collecting pearl oysters and seafood by diving was a very common occurrence throughout the world. From the Ama divers in Japan and Korea to the Mayans and even the native American Indians, diving has always been a boundary that humans were always trying to break.