He calls it "the yellow brick road" because it's literally sprinkled with gold dust.
This road runs along Cape Cod's shifting seafloor, and undersea explorer Barry Clifford believes it leads to undiscovered treasure from the wreck of the pirate ship Whydah.
About two weeks ago, Clifford and his dive team took a trip back to the wreck site, and Clifford returned more convinced than ever that the road he's exploring is a path to riches.
"We think we're very, very close," he said.
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The Whydah sank in a brutal storm in 1717 with plunder from 50 ships on board. Clifford discovered the wreck site in 1984 off Wellfleet and has since pulled up 200,000 artifacts, including gold ornaments, sword handles, even a boy's leg.
But just this year, Clifford learned far more treasure may be resting with the Whydah, the only authenticated pirate shipwreck in U.S. waters.
Colonial-era documents discovered in April indicated the Whydah raided two vessels in the weeks before it sank. Its haul on those raids included 400,000 coins, the records said.
A Sept. 1 dive during what was supposed to be Clifford's last trip of the season uncovered evidence he was near those coins. That convinced Clifford he had to make another trip before summer's end. So Clifford and a seven-man crew went back on a three-day trip that ended Sept. 13.
Clifford headed for the "yellow brick road," which refers to a gold and artifact-strewn path extending between two significant sites at the Whydah wreck that are about 700 feet apart — a cannon pile and a large chunk of wood that Clifford thinks is the Whydah's stern.
The trove of coins and other treasure likely poured from the stern as the ship broke up and the stern drifted to its rest 300 years ago, he said.