JERUSALEM -- Israeli lifeguards plunged into the Mediterranean sea this month on an unusual rescue mission: to pull out an ancient ship's anchor.
Lifeguard Avi Afia first spotted the tip of the anchor on a daily swim five years ago. It was peeking out from the sandy ocean floor about 150 feet from the coast.
It wasn't until this month that the sands shifted to reveal the treasure in its entirety: a nearly 7-foot, 650-pound iron anchor, probably a spare in the belly of a Byzantine ship that crashed and sank in a storm about 1,700 years ago, said archaeologist Jacob Sharvit of Israel's Antiquities Authority.
"It's a feast for the eyes," said Afia, whose colleagues walked out to the spot, in water about six feet deep and dragged it into the lifeguard shack in Bat Yam, near Tel Aviv.
The anchor dates back to the 4th or 5th century, estimated Sharvit, who heads the marine archaeology branch of Israel's Antiquities Authority.
He said it attests to the vibrant sea trade of the Byzantine era, when merchant ships would carry oil, wine and stones for construction to ports along the coast and across the Mediterranean. The anchor also may point to a previously unknown ancient harbor on the coast, he added.
He said his team of archaeologists would go diving this week to search for the rest of the shipwrecked treasure. He expects to find ancient wine and oil jugs, coins, the seafarers' personal items -- and more anchors.
Shipwrecked finds, while not rare, are especially valuable for archaeologists, Shavit said. Ancient ships often carried brand-new items on their way to be sold in markets. That means researchers can examine those items in their original condition, before they were used.
The collection of items found on the ocean floor also tells a complete story of the seafaring routes and technological advances of that moment in history.
"It's like a time capsule," Sharvit said. "Every find, especially in the sea, tells a story of disaster."
The region's 5,000 years of seafaring have seen numerous tragedies. Every few days, Sharvit's divers discover remnants of sunken ships on the ocean floor. So far they've found 500 groups of shipwrecked items along Israel's coast, though he said the anchor is among the most impressive finds.
A particularly strong storm at the end of 2010 moved large amounts of sand, unearthing ancient objects close to the coast. A passer-by on the beach in Ashkelon, south of Tel Aviv, found a 4-foot tall white marble Roman statue of a woman in a toga and sandals on a cliff that had crumbled under the weight of strong winds and high waves.
The rise in discoveries also led to an increase in looting, Sharvit said. They include scuba divers who go looking for treasure to sell on the black market, as well as fishermen who discover antiquities in their nets and take them home along with the fish.
Looters caught face a possible three-year prison sentence, according to Sharvit.
But the "Indiana Jones" lifeguards are being given a hero's welcome.
"We knew it was there for years," Afia said. "We're happy and proud to give it as a gift."