<p><strong>As drought depleted <a href="http://travel.nationalgeographic.com/travel/countries/poland-guide/">Poland</a>'s <a href="http://maps.nationalgeographic.com/map-machine#s=h&amp;c=52.2498747240591, 21.03452682495117&amp;z=12">Vistula River (map)</a>, tons of looted 17th-century marble artifacts—including this stonework pictured against a power plant—surfaced this month. The revelation helps solve a centuries-old mystery and crowns one archaeologist's three-year quest for <a href="http://travel.nationalgeographic.com/favorites/poland/warsaw/">Warsaw</a>'s lost royal treasures.</strong></p><p>The sculpted fountains, columns, and other marbles on the muddy bottom of the Vistula—now at its lowest level since record keeping began in the late 1700s—once decorated <a href="http://www.zamek-krolewski.pl/">Warsaw's Royal Castle</a>, Kazimierz Palace, and other haunts of Polish nobility. Stolen during the multiyear conflict known as the Swedish Deluge, the treasures were lost when a getaway barge sank while setting out for <a href="http://travel.nationalgeographic.com/travel/countries/sweden-guide/">Sweden</a>.</p><p>"So far we have found more than 12 tons of original, 17th-century marbles," said<a href="http://www.muzeum.uw.edu.pl/2011/03/28/wice-dyrektor-dr-hubert-kowalski/"> Hubert Kowalski</a>, the University of Warsaw archaeologist leading the search. "They are in very good shape, considering 350 years in the river."</p><p>(Related <a href="http://news.nationalgeographic.com/news/2012/08/120803-pictures-surprising-effects-of-us-drought/">pictures: "Surprising Effects of U.S. Drought."</a>)</p><p><em>—Brian Handwerk</em></p>

Many Faces of Power

As drought depleted Poland's Vistula River (map), tons of looted 17th-century marble artifacts—including this stonework pictured against a power plant—surfaced this month. The revelation helps solve a centuries-old mystery and crowns one archaeologist's three-year quest for Warsaw's lost royal treasures.

The sculpted fountains, columns, and other marbles on the muddy bottom of the Vistula—now at its lowest level since record keeping began in the late 1700s—once decorated Warsaw's Royal Castle, Kazimierz Palace, and other haunts of Polish nobility. Stolen during the multiyear conflict known as the Swedish Deluge, the treasures were lost when a getaway barge sank while setting out for Sweden.

"So far we have found more than 12 tons of original, 17th-century marbles," said Hubert Kowalski, the University of Warsaw archaeologist leading the search. "They are in very good shape, considering 350 years in the river."

(Related pictures: "Surprising Effects of U.S. Drought.")

—Brian Handwerk

Photograph by Kacper Pempel, Reuters

Pictures: Lost Royal Treasure Revealed by Sinking River

Looted—and promptly lost—350 years ago by invading Swedes, tons of monumental marble artifacts come to light as a Polish river withers.

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