Shown on September 9 in central Warsaw, the Vistula River had hidden its contraband marble since the mid-1600s, when a shipwreck sent tons of stolen royal marbles to the bottom.
References to the lost loot appeared in 17th-century letters, Kowalski, the archaeologist said. His own search started in 2009, when he began studying 1906 documents depicting marble finds in the river-pictures, newspaper articles, and other accounts.
"Workers trying to dig sand out of the river found marbles, which I think were from exactly the same boat," he explained. "All the things they found were within a one-square-kilometer (0.4-square-mile) triangular area, which in the beginning of the 20th century was defined by three small towns. Now it's all in Warsaw."
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