Ancient mass graves containing more than 1,500 victims of the bubonic plague have been discovered on a small island in Italy's Venetian Lagoon.

Workers came across the skeletons while digging the foundation for a new museum on Lazzaretto Vecchio, a small island in the lagoon's south, located a couple of miles from Venice's famed Piazza San Marco.

The island is believed to be the world's first lazaret—a quarantine colony intended to help prevent the spread of infectious diseases.

The lazaret was opened during the plague outbreaks that decimated Venice, as well as much of Europe, throughout the 15th and 16th centuries A.D.

Its presence may have helped Venice recover more quickly during the devastating outbreaks.

"When plague struck the town, everybody sick