BELGRADE, May 5, 2010 -- The cold depths of the Adriatic Sea have yielded yet another bonanza -- and it's not fishing. Scuba divers are now able to plunge into the sea's clear, astonishingly blue waters and see ancient treasures protected by a giant underwater safe.
An ancient Greek shipwreck containing treasure with an estimated value of about $8 million is accessible to divers just off the coast of the off the coast of the Croatian town of Cavtat. Included in the wreck are hundreds of clay amphoras, the storage jars of antiquity, probably once filled with wine and oil, lie just 96 feet below the water's surface.
"Although the shipwreck is destroyed, the cargo of the wreck appears to be pristine," Boris Obradovic, the head of "Epidaurum" Scuba Diving Center, who found the shipwreck in 1999, and now guides experienced scuba divers down to the wreckage, told ABC News.com.
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A striking video made by Obradovic and his team shows "a mixture of gray, brown and reddish amphoras much like they were placed shortly after the ship settled into the ooze." Some amphoras are encrusted with purplish sponges, others with algae and feathery hydroids.
After studying the videos with nautical archaeologists, Marijan Orlic, an underwater archaeologist and retired director of operations for Croatian Conservation Department, tentatively identified the jars as typical of the African origin, near modern day Tunis, around the third century AD.
A steel mesh cage the size of a volleyball field shields the wreck, which is about 67 feet long and 35 feet wide. At least 700 amphoras are visible above the seabed.
"It's an incredible find," Orlic said in an interview from Zagreb. ''It's the biggest shipwreck we ever found. We were very excited, but had to protect it from the looters, so we chose to physically protect it with a metal cage."
"What lies beneath the amphoras and the ooze -- whether the ship's wooden hull, tools or personal items, which would help identify important archaeological information -- can only be learned by excavation," Orlic continued. "No Croatian archaeologist can afford the millions it costs to probe it. Luckily, the cold water and low oxygen levels of the sea keep many items well preserved."
Underwater photographer Neil Hope was among those given permission to dive the wreck with Obradovic.
"I'm an experienced diver and I've dived wrecks all over the world, but this was the most unique experience," Hope said.
"Obviously, when you are inside you can't touch any of the cargo as it is very valuable, so they don't just let anyone inside the cage. You need excellent buoyancy skills so you're not damaging these valuable things.''
Archaeology is "a luxury like art," Obradovic said ''It is hard to make it pay for itself without losing some of its foundations, but a decision to give scuba diving tourism a chance was a very good one."