Marine archeologists using an undersea robot to prowl the Mediterranean Sea floor discovered what may be the largest concentration of ancient shipwrecks ever found in the deep sea, one of them a Roman ship dating from before the time of Christ, the researchers announced Wednesday.
The discovery, which spans more than 2,000 years of human history, offers an unusual glimpse into mankind's maritime past, experts in marine archeology said. Contrary to previous thinking, the wrecks in deep water off Sicily demonstrate that ancient sailors did not hesitate to leave the shelter of coastal waters and venture onto the open sea.
Led by Robert Ballard, whose previous underwater explorations included the discovery of the Titanic and the German battleship Bismarck, the expedition found a cluster of eight ships and thousands of artifacts scattered on the sea floor half a mile below the surface of a previously unknown early trade route between Italy and North Africa.
The find includes five Roman ships, which from their cargo and their design appear to date from between 100 BC and AD 400, one Islamic ship from the late 18th century and two more modern ships lost about a century ago. The discovery was announced Wednesday at a news conference held by the National Geographic Society, which funded part of the $1-million expedition.
"It is very impressive," said nautical archeologist George F. Bass at Texas A&M University, who has explored hundreds of Mediterranean shipwreck sites. "That [Ballard] found so many in such a small area is impressive; that he can explore them at such depth is impressive.
"I was surprised there were so many wrecks visible in the open sea," Bass said. "These ships are lying out as if they had landed on the seabed only a few days ago."
Experts said this was the first major ancient shipwreck site to be discovered or explored in water deeper than 200 feet. The advanced technology used by Ballard's group allows archeologists to explore down to 20,000 feet deep--the depth of 98% of the oceans--opening a new window into the past.
The average depth of the Mediterranean is 9,000 feet, with some of the areas most heavily trafficked by ancient mariners--such as portions of the sea off the coast of Greece--reaching depths of 20,000 feet.
"I think the deep sea holds more history than all of the museums of the world," said Ballard, who is president of the newly organized Institute for Exploration in Mystic, Conn.
Describing the oldest Roman wreck, Ballard said in an interview that the eerily tranquil fields of debris on the sea floor 2,500 feet below the Mediterranean surface were testament to the desperation of sailors facing a maritime calamity. A distinctive trail of debris, he said, indicated that the Roman crew, racing to outdistance a squall, threw cargo overboard in a valiant but vain effort to lighten their storm-tossed ship before high seas swamped the craft.
The expedition's deep-diving robot followed the trails of remains directly to a remarkably well-preserved vessel perhaps 100 feet long, with two cargo holds fore and aft of the mast.
When Ballard first discovered the 20-square-mile artifact site in 1989, it seemed so large--20 times broader than the disarray he had encountered earlier around the wrecks of the Titanic and the Bismarck--that he assumed he had stumbled across the remains of an entire fleet that had foundered in the same storm.
"We thought we were looking at one moment in human history," Ballard said. When the expedition explored the site this summer, however, "what we found were lots of ships, as we expected, but it was a graveyard of ships spanning two millennia."
The expedition was the result of an unusual partnership between the U.S. Navy's Office of Naval Research, its Office of Deep Submergence Systems and a team of civilian engineers, oceanographers and archeologists.
A U.S. Navy nuclear submarine--the NR-1, commanded by Lt. Cmdr. Charles Richard--used long-range sonar to locate the site for the research team, which then used the remotely piloted vehicle Jason from the Woods Hole Oceanographic Institution to explore the wrecks.
The NR-1--a wheeled undersea rover that can stay submerged on the sea floor for a month at a stretch--carries sonar that can detect shipwrecks on the ocean floor at much greater distances than equipment normally available to oceanographers.
Once the oceanographers had mapped the area--building a computerized three-dimensional model of the scene--the team explored the site at leisure.
There, under a thin blanket of silt, the ships were preserved out of harm's way, secure from the currents that tumbled shipwrecks closer to shore into ruin.